JPH06282918A - Optical disc library unit - Google Patents

Abstract

(57) [Summary] [Purpose] The objective is to improve the speed, reliability, and flexibility of the optical disk library unit. The system includes at least one pair of disk drives, a device for holding a portion of a cartridge within the disk drive, and a dual picker assembly. The operation of the stepper motor can be programmed according to the characteristics of the disk drive. The unit alignment and calibration system includes both a mechanical alignment system and an optical alignment system. The unit has an optical sensor that detects interruption of picker movement. The control electronics are arranged so that the picker operations are performed in parallel. Also, the control electronics are configured such that the operations performed by the unit are determined based on execution speed or equalization of component wear.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to electronic document retrieval systems, and more particularly to optical disc libraries for document storage and retrieval.

[0002]

BACKGROUND OF THE INVENTION Binary data can be stored at much higher densities on optical recording media than on magnetic media. For example, an optical disk with a diameter of 5.25 inches (about 13.3 cm) can store up to 650 million characters, while a magnetic recording disk with the same diameter can store up to 200 characters. It is less than 10,000. Therefore, optical discs are increasingly used for electronic storage of very large documents or records. The records of large insurance companies, large national banks or corporate companies such as airlines contain billions of characters. Therefore, although optical discs have high storage capacity, large numbers of optical discs are required to store the records and references of large corporations. Similarly, libraries of optical discs need to store such records.

Users of electronic data storage systems are accustomed to the speed and convenience of retrieving records and references in such systems. Therefore, the optical disc library should be able to obtain similar speed and convenience. For those companies that rely on such systems, document retrieval speed is a measure of their productivity. In order for an optical disc library to be accepted by large scale storage and retrieval systems, the optical disc library must have the speed and reliability appropriate for its large storage capacity. The optical disc library unit requires a storage capacity of a plurality of discs, one or more optical disc drives for reading or writing the discs, and a mechanism for moving the discs in and out of the storage device and in and out of the drive (disc drive). It is said that The movement and placement of the disks must be done automatically (robotically), and this automatic movement must be fast, accurate and reliable.

Optical disks are typically housed in a thin, flat rectangular housing or cartridge. The cartridge protects the disc when not in use and facilitates insertion of the disc into the drive for reading data from or writing data to the disc. Various media are used for disks, depending on whether they are only read from the disk or both read and write. Optical disc cartridge
All cartridges from different manufacturers have been standardized to have essentially the same physical properties despite the use of different media. Unfortunately, optical disc drives have not yet been fully standardized. More specifically, the loading and unloading characteristics of a drive depend on various drive types and manufacturers.
Wide range is different. For example, the relative position of the access slot (ie, the distance between the drive's access slot and the bottom), the accuracy with which the cartridge should be placed for loading, the mechanical resistance due to springs that must be overcome to load the cartridge into the drive, etc. Varies greatly depending on the drive type.

Another problem is the ejection of a cartridge from a disk drive. For example, the distance that the automatic ejection mechanism of each disk drive pushes the cartridge out of the access slot is not standardized. For this reason, it becomes difficult to automatically take out the cartridge from the disk drive, and it interferes with the movement of the automatic takeout mechanism. Also, the automatic eject sequence requires a certain amount of time for the automatic eject mechanism to perform other tasks. Also, optical disc drive manufacturers do not allow modification of the disc drive housing or load / unload mechanism to facilitate automatic loading and unloading. If such a modification would void the warranty on the disk drive, and the manufacturer knew that such a modification would be made, the manufacturer would not sell their drive. Therefore, if the optical disc library does not have the flexibility to adapt to these various formats, it will slow down, stop frequently, and damage the disc or cartridge.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to an apparatus for storing optical data disk cartridges. It is therefore an object of the present invention to improve the speed, reliability and flexibility of optical disc library units.

[0007]

SUMMARY OF THE INVENTION In a preferred embodiment, the apparatus of the present invention comprises a rack with a plurality of generally parallel storage slots for storing cartridges. At least one disk drive pair is attached to the rack. The disk drive pair has two optical disk drives, and each drive has an access slot for inserting and removing a cartridge. Mounted on each access slot is a mechanism that holds a portion of the cartridge within the access slot after the cartridge is removed by the disk drive. The drives are mounted vertically adjacent to each other. The device of the present invention also has two pickers for transferring cartridges between selected positions on the rack. These pickers are assembled together in a back-to-back relationship. Each picker includes a flat actuator that releases the cartridge from a cartridge retention mechanism mounted on the access slot of each disk drive, and a gripping device that inserts the cartridge into and out of the slot. Each gripping device is provided with a releasable holding grip for holding the cartridge.

The device of the present invention comprises a drive system for moving the picker from one position to another, rotating the picker, and actuating the gripping device and the holding grip.
This drive system is the first to move the picker in the X direction.
The motor comprises a motor, a second motor for moving the picker in a Y direction perpendicular to the X direction, and a third motor for rotating the picker around a Z axis line perpendicular to the X and Y directions.
The drive system further comprises two gripper drive motors (one drive motor for each gripper) and two solenoids (each solenoid actuates a holding grip). A controller communicates drive commands to the drive system to control the motor. The device of the invention comprises a slot,
It has an alignment system that maps the position of the cartridge in the drive and rack. The alignment system includes a plurality of sensors that determine each position of a plurality of fixed reference points. The alignment system also includes the position of each slot in the rack,
And a sensor for detecting the position and type (ie, brand) of each optical disk drive. Also,
These sensors are also used to determine which slot contains a cartridge and to map the position of the cartridge receiving slot.

The locations of slots, drives, cartridge receiving slots and reference points are tabulated in the central processor and actually form a map of said locations. This map can be configured to be updated whenever the disk is moved. The central processor comprises means for determining a set of commands to move the cartridge in the path between the selected positions. The command can include, for example, a path along which the picker should be driven.

[0010]

The accompanying drawings, which are incorporated in and form a part of the specification of the present invention, schematically illustrate preferred embodiments of the invention, and which are set forth in the above general description and set forth below. The principle of the present invention will be explained together with the detailed description. Referring to the accompanying drawings, in which like components are designated by the same reference numerals, FIGS. 1, 2, 3 and 4 show an optical data disk library unit according to the present invention.
A preferred embodiment of a k library unit (ODLU) is shown. The ODLU is generally designated by the reference numeral 20. The ODLU 20 has a base 22 and a top 24 that are supported by a generally rectangular frame 26. Normally, the ODLU 20 is completely closed by the side panel. To show the important features of ODLU20,
Illustrations of these panels have been almost completely omitted. ODLU
A portion of panel 28 is shown in FIG. 2 to show some 20 control means (discussed below).

A vertical rack member 30 is mounted between the top portion 24 and the base portion 22. The rack member 30 is arranged to form five bays or columns 32A-32E (each column of equal width) for supporting a plurality of slots 34. Each slot 34 has one IS
It has a size suitable for an O standard 650 megabyte (650 Mb) 5.25-inch optical disk cartridge (see FIG. 2, hereinafter simply referred to as a cartridge). Slots 34 are preferably located within bays 32A-32E of adjacent modules 36 (see FIG. 2). The module 36 can be formed of, for example, injection molded polystyrene. When grouping slots into relatively small modules as described above, due to warpage and distortion,
It has been decided to tighten manufacturing tolerances and degrees of freedom.

Referring in detail with reference to FIG. 1, each module preferably has twelve slots. Collective bays 32A-32E with modules 36
A complete rack 21 of generally parallel spaced storage slots for storing optical disk cartridges is constructed. The rack 21 stores up to 288 cartridges. Sensor holes 42 are disposed on the outer end 40 of the module 36 adjacent to both ends of each slot 34, and the line between the sensor holes is substantially parallel to the slots 34 (see FIGS. 3 and 4). . Sensor hole 42
Is part of the optical alignment and mapping structure (detailed below). Two optical disc drives 44 are attached to the bay 32. Each drive 44
Has an access slot 46 for inserting and removing a cartridge that is read or written by the drive 44. The drives 44 are mounted one above the other without any intervening cartridge slots 34 between them, forming a drive pair 47.

The ODLU 20 is constructed such that one drive pair 47 is attached to each of the bays 32A to 32E (see FIG. 1). Therefore, the ODLU 20 can be provided with five drive pairs 47 at the front, ie ten drives 44. The drives may be functionally different, but preferably each drive has a full-height form factor of 5.25 inches and a side mount. The 5.25 inch shape factor is a provisional standard adopted in the computer industry for both magnetic and optical recording media drives. However, the relative position of the access slot 46 (ie, the distance between the access slot 46 and the bottom of the drive 44) can be varied according to various specifications of the drive.

Each drive pair 47 occupies one position in bay 32 (this position is occupied by module 36 if drive pair 47 does not occupy). The drive pair 47 is preferably mounted in place of the central module of the column to provide equally easy access to the upper and lower slots or cartridges of the drive pair 47. The drive slots 46 are parallel to each other and are preferably spaced the same distance as the seven slot spacing of the slots 34 of the module 36. Referring now to FIG. 4, the original bezel provided on the drive 44 is removed from the drive 44 and each drive 44 is provided with a replacement bezel 414. The bezel 414 has sensor holes 42A and 42B separated in the width direction by the same distance as the sensor hole 42 of the module 36. These sensor holes 42A, 42B are used by the alignment system to map the position and type of individual disk drives.

Sensor hole 42A is used to indicate the presence of a disk drive. as mentioned above,
The relative position of the access slot 46 can be changed according to various specifications of the drive. Therefore, the sensor hole 42
The number and relative position of B's are used by the alignment system to identify up to 16 specifications (or types) of drives. This allows drives with different specifications to be used with the ODLU20.
Can be used simultaneously in. Drive 4
The cartridge holding mechanism 400 is arranged in front of the access slot 46 of No. 4. The retention mechanism 400 is attached to the vertical rack member 30 to avoid obstructing the drive casing 402 of the disk drive 44. The cartridge holding mechanism 400 includes a bar 404 and a spring biasing roller 406. Cartridge 38 is drive 4
When removed from slot 4 of four, cartridge 38 is held in the partially removed position by rollers 406 (ie, the spring of disk drive 44 continues to exert pressure on cartridge 38, see FIG. 16).

Referring again to FIG. 2, a double picker assembly 48 is provided for inserting and removing disks from the cartridge slot 34 and drive slot 46. The picker assembly 48 has two pickers 49 that are assembled together in a back-to-back relationship. Each picker 49 has a gripping device (grabber) 51 for gripping a standard 5.25-inch optical disc cartridge.
have. The gripping devices 51 are spaced by an exact multiple of the slot spacing. The picker assembly 48 is rotatably mounted to the picker assembly mounting unit 50 by a shaft 54 and a circulating ball bearing type bearing.
The picker assembly 48 can be configured to rotate about axis Z so that either picker 49 is on top. The picker assembly 48 is manufactured by MFM Corporation (Ronkomkona,
It is rotated by a servomotor 60, such as the model SM 44 available from New York. Servo motor 60 drives shaft 54 via a worm gear drive. For clarity, details of the servo motor drive are shown in FIGS.
Omitted from. These details are well known to those skilled in the art.

The picker assembly 48 and the picker assembly mounting unit 50 are mounted on the transfer frame 64.
The transfer frame 64 has a base 66 and a top 68 attached to generally parallel spaced support rods 70. The base portion 66 and the top portion 68 (see FIG. 2) are slidably mounted on support rods 72 and 74 arranged on linear bearings (not shown), respectively. The transfer frame 64 is moved in the direction indicated by arrow X, that is, the X-axis (see FIG. 1), by means of a lower chain drive 76 mounted on the base 66 of the transfer frame and an upper chain drive 78 mounted on the top 68 of the transfer frame. ) Is moved along. Power for the chain drives 76, 78 is provided by a single servomotor 80 (e.g., model SM 64 commercially available from MFM Corporation). The servo motor 80 is connected to the sprocket and chain reduction gear drive device. The servomotor 80 has a shaft 77
The upper and lower chain drive devices 76 and 78 are simultaneously driven by sprockets 75 (only the upper sprocket is shown in FIG. 1) attached to both ends of the chain.

The picker assembly mounting unit 50 is slidably mounted on the transfer frame 64 via a bushing 90 which is slidably mounted on a vertical rod 70. The chain drive 92 mounted on the mounting unit 50 allows the mounting unit 50 and thus the picker assembly 4 to be mounted.
8 is moved in the direction indicated by arrow Y, that is, along the Y-axis line that is perpendicular to the X-axis line. Rotation axis Z of the picker assembly 48
Is perpendicular to both the X and Y axes. The chain drive 92 is driven by a servomotor 94 mounted on the base 66 and connected to a sprocket 96 via a chain drive (not shown). A balance counter weight 69 is attached to the chain drive device 92. The ODLU 20 has a so-called mailbox system 100 in which a cartridge is inserted into (and taken out from) a predetermined position of the rack 21 (and from a predetermined position). This mailbox is a well-known feature of prior art optical disc library units, but for the sake of completeness it will be briefly described below.

The mailbox 100 is a platform 1 for placing a cartridge to be inserted in the ODLU 20.
Have 02. The platform 102 has a rectangular recess (not shown) for holding the cartridge. Platform 102 is linear bearing 10
It is slidably mounted on parallel support rods 104 via 3. A motor 112 attached to the belt drive 113 drives a lead screw (not shown) that moves the platform 102 forward or backward. When inactive, the mailbox 100 rests with the platform 102 on top of the column 32E, as shown in FIG. When the mailbox 100 is biased, the platform 102 is driven along the support rod 104 through the slot 106 in the side panel 28 (see FIG. 2).
The cartridge is then placed on the platform 102 and the platform 102 is returned to the rest position at the top of the column 32E. Here, the picker assembly 48 accesses the platform 102 and the platform 102 moves into position within the rack 21. Similarly, the cartridge is removed by the picker unit 48 into place on the rack 21 and placed on the platform 102 at the top of the column 32E. The platform 102 is then driven to position 108 and the cartridge 38 is removed.

The above arrangement for driving the transfer frame 64 and the picker assembly mounting unit 50 is the picker assembly 48.
To drive the picker assembly 48 adjacent to the cartridge or drive slot of the rack 21 by driving both the X and Y directions. Also,
The picker assembly 48 rotates about a Z axis that is perpendicular to the X and Y axes, such that the preferred side of the picker assembly 48 is up. Details of the picker assembly 48 are described below. 5, 6, 7, and 8, details of the dual picker assembly 48 are shown.
As previously mentioned, the picker assembly 48 has two pickers 49 that are assembled together in a back-to-back fashion.
Although the pickers 49 are described as being separate entities, it is convenient to assemble the pickers 49 together on a common frame 120.

The frame 120 has two parallel side walls 122.
(FIGS. 5 and 6). The side wall 122 includes two bulkheads (partition walls) 124 (see FIGS. 6 and 7) of the rotating shaft, two rear brackets 128 (see FIGS. 6 and 7) for the step motor or drive screw, and a drive screw. The bulkhead 124 is separated by two front brackets 130 (only one of which is shown in FIG. 8).
Installed on. The rotary drive shaft 54 (only shown in FIG. 5) that rotatably mounts the picker assembly 48 to the mounting unit 50 (FIG. 2) has a bulkhead 124.
1 through the hole 125 (see FIG. 7) of the
It is attached to 25. Although important features of common frame 120 have been described, pickers 49 are essentially the same as each other, so only one picker 49 will be further described below.

Continuing to refer to FIGS. 5, 6, 7 and 8, gripper assemblies 51 are supported on support rods 132, which are supported by support rod brackets 134 on each side wall 122. Installed. The side members 140 of the gripping assembly (see FIGS. 5 and 7 for more details) include linear bearings (not shown) within the support rod 132.
It is slidably supported on the support rod 132 via. An attachment platform 142 is attached to the side member 140 of the grip assembly 51 (see FIGS. 6 and 7). Brackets 144, 1 on the platform 142
A solenoid assembly 150 is attached via 46, and the solenoid assembly 150 has a solenoid 151 for operating the gripping device 51. Referring to FIG.
Actuator mounts 412 are further attached to the platform 142 on both sides of the solenoid 151. Below the platform 142, the actuator mount 412 has two spring-loaded flat actuators 408 mounted thereon that release the cartridge 38 from the cartridge retainer mechanism 400 by a pressure roller 406. Used for. Flat actuator 408
Is mounted such that one actuator 408 is mounted above the plane formed by the gripping jaws 158 and one actuator 408 is located below said plane (see FIGS. 5, 17 and 18).

Continuing to refer to FIGS. 5 and 6, the solenoid assembly 150 is pivotally attached to one end of each of the two gripper actuating arms 154 via links 152. At the other end of these actuation arms 154, each actuation arm 154 is attached to a pivot rod 156.
With reference to FIG. 6, each pivot rod 156 extends through the side member 140 of the gripper so that the gripping jaw 158 is clamped to the rod 156. In the preferred embodiment, each grasping jaw 158 has a rear stop 160 for positioning the rear of a standard 5.25-inch optical disc cartridge (outlined by dashed line 38), a grasper arm 420, and the sides of the cartridge. And a spring-biased collapsible key 162 that engages the notch. The collapsible key 162 is pivotally attached to the gripper arm 420 by a pin 410. The collapsible key 162 is crushed inward as the key 162 engages the side housing 402 of the drive 44 during loading of the cartridge 38 into the disc drive 44 (ie, the longitudinal axis of the collapsible key 162 is grasped by the grasper arm 420). Parallel to the longitudinal axis of. In another embodiment, each grasping jaw 158 is
It has a rear stop 160, a gripper arm 420, and a locking key (not shown) that engages a notch on the side of the cartridge 38.

When the solenoid 151 is not energized, the collapsible key 162 clears (passes) the cartridge 38. When the solenoid 151 is energized, the link 152 is pulled toward the solenoid assembly 150 and the gripping jaws 158 are closed tightly to close the cartridge 38.
Hold. The solenoid 151 is then de-energized and the cartridge 38 is released. 16, 17 and 18, the cartridge 38 is released from the retainer mechanism 400 by a spring biased flat actuator 408 that engages a spring biased roller 406. The roller 406 is pushed rearward and upward by the flat actuator 408, and is removed from the passage. The spring of the disk drive 44 used to eject the cartridge 38 then forces the cartridge into the waiting grip jaw 158. The unused flat actuator 408B that is not used to engage the roller 406 moves forward toward the disk drive 44, while the flat actuator 408 moves forward. because,
Both are attached to the same platform 142 (via the actuator mount 412).

However, the unused flat actuator 408B is prevented from entering the electrical portion of the disk drive 44 (the portion that crushes the unused flat actuator 408B) by the actuator stopper 416 attached to the bezel 414. Unused flat actuator 408B and actuator stopper 41
6 is disengaged, the spring (not shown) of the unused flat actuator 408B returns the unused flat actuator 408B to its original extended position. The spring constant of the spring (not shown) of the flat actuator 408 is larger than the spring constant of the roller spring 418 attached to the roller 406.
Is engaged with the roller 406 to retain the retainer mechanism 400.
It does not collapse when the cartridge 38 is released from.

In order for the cartridge to be transported between selected positions of the ODLU 20, the cartridge must be pulled into the picker 49 by the gripping device 51. The back and forth movement of the gripping device 51 for pushing or pulling the cartridge is achieved by means of a threaded lead screw or drive screw 170 (see FIG. 6). Drive screw 1
70 has one end rotatably held by the drive screw front bracket 130 (see FIG. 8) and the other end extending through the drive screw rear bracket 128, to which the pulley 172 is attached. There is. Further, the front bracket 130 for the drive screw and the rear bracket 128
Between the drive screw 170 and the mounting platform 1
It extends through a threaded bushing 174 attached to the underside of 42 (see FIG. 8). When the pulley 172 is rotated in one direction, the gripper assembly 51 with the actuating arm 154 and the jaw 158 moves toward the rear of the picker 49 (ie, from the position shown as FWD in FIG. 5 to the position shown as AFT). ) Pulled (lower grip assembly 5 in FIG. 5)
1). When the pulley 172 is rotated in the opposite direction, the gripping assembly 51 can move forward, for example to exchange rotation in the slot.

The slot 180 in the sidewall 122 allows the gripping jaws 158 to pass through when the gripping assembly 51 is moved. When the cartridge is pulled into the picker 49 by the gripping device 51, it slides between the cartridge guides 182 and rests on it. The cartridge guide 182 is attached to the side wall 122 inside the picker 49. Guides 182 are provided above and below each slot 180 of the picker 49. In Figure 6,
Two guides 182 are shown. The back-and-forth movement of the gripping device 51 is limited by a back-and-forth limit sensor 186 (only shown in Figure 5). The cartridge is Picker 4
A sensor 184 is provided to indicate this when it is inside 9 (see the broken portion in FIG. 8). In the ready position, the gripping device 51 is almost fully extended and at rest and the jaw 158 is retracted within the slot 180 by about 1/4 inch. The sensor 187 displays the ready position.

Attached to each sidewall 122 is an optical sensor 185 (see FIG. 5) having an infrared emitter and an infrared detector for detecting and receiving optical signals. Figure 5
Although (and in FIG. 2) only one sensor is shown in FIG. 2, another sensor can be placed at the same location on the opposite side of the picker assembly 48. Separating the two photosensors separates the sensor hole 42 (see FIGS. 3 and 4).
(Refer to) are separately arranged in the lateral direction. These sensors are used for alignment and calibration of the ODLU 20. The pulley 172 of the drive screw 170 is, for example, a Portescap company (La Chaux-de-Fonds, S, via a pulley 192 and a drive belt 194).
It is driven by a stepper motor 190, such as the model p532 available from Witzerland. The stepper motor 190 is attached to the drive screw rear bracket 128 on the side opposite to the pulley 172.

The stepper motor 190 operates at a variable speed with information programmed to match the loading and unloading resistance of any optical data disk drive, even though the loading and unloading resistance characteristics are different. Further, when the stepper motor 190 encounters an abnormal excessive resistance, the stepper motor 1
90 continuously slips, and this state is generally called cogging. In this cogging state,
Although the magnetic field mechanism of the motor continues to rotate, the motor shaft does not respond to the rotation of the magnetic field. The stepper motor 190 performs the encoder's programmed count amount and then stops. The stepper motor 190 does not try to overcome the excessive resistance. Therefore, the gripping device 51 driven by the stepper motor 190 contributes to a reduction in the possibility of damage to the cartridge and the drive and a high reliability of the ODLU 20.

The components of the alignment and calibration structure will now be described with reference to FIG. 9 and again with reference to FIGS. The alignment system of the ODLU 20 includes a switch arm or mechanical flag 20 mounted on the base 66 of the transfer frame 64.
Has 0. As shown in FIG. 9, the lower sensor bar 202 has a slot type optical sensor 204. Each sensor 204 has a light emitter and a photodetector (not shown). The sensor 204 is activated as the switch arm 200 passes between the light emitter and the photodetector. The sensor 204 is arranged at a position aligned with substantially the center of each bay 32A to 32E. At each end of the contact bar 202, a sensor 204 that determines the X-direction movement limit of the transfer frame 64 is provided.
Is also arranged. By arranging the slot type optical sensors 206 and 207 in the pickup assembly mounting unit 50, a similar structure for determining the upper and lower movement limits of the picker assembly 48 on the Y axis is obtained. Upper sensor 20
6 is urged by the switch arm 201 arranged on the top 68 of the transfer frame 64, and the lower sensor 207 is urged by the switch arm 203 arranged on the base 66 of the transfer frame 64.

The picker assembly mounting unit 50 is also provided with a slotted optical sensor 205 (see FIG. 1) for determining the encoder count of the Z (rotation) drive motor 60 corresponding to the level alignment of the picker assembly 48. ing. The slot type optical sensor 209 is provided in the picker assembly 4
Display the rotation limit of 8. The sensors 205, 209 are biased by a switch arm (not shown) attached to the shaft 54. Referring again to FIG. 9, the lower sensor 20
2 is also provided with a light emitter 208. Each light emitter 208
Is preferably located approximately in the center of each bay 32A-32E. These light emitters 208 are shown somewhat displaced from the center of the bays 32A-32E for convenience of illustration.
The light emitter 208 is preferably an infrared light emitter such as model MTE 1100 available from Mark Tech, Inc. (Latham, NY). On the upper sensor bar 210, a detector 212, such as the model MTE 6100 available from Mark Tech, Inc., is positioned in substantially vertical alignment with the light emitter 208 on the sensor bar 202. Each emitter 208 and its corresponding detector 212 have a line of sight between them, indicated by dashed line 214 in FIGS. 2 and 9, when the cartridge 38 is properly seated within the slot 34.
It is positioned to pass 1/4 inch (about 6.4 mm) from the trailing edge.

During normal operation of the ODLU 20, the pickers 49 are in a rest position when they are empty, and the gripping jaws 158 are about 1/2 inch from the cartridge 38 when they seat properly in the slots 34. (Approximately 13 mm)
Located in a remote location. This is to minimize the time required to take out the cartridge from the slot after receiving the command. In prior art library units in which the gripper is driven by a servomotor, actuation of the gripper is usually initiated from the fully retracted position. The cartridge 38 is 1 from its proper position.
If the cartridge 38 is improperly placed in the slot 34 or inadvertently removed from the slot so that it projects more than 1/2 inch (about 13 mm), the cartridge 38 blocks the line of sight 214. This interruption is detected by an appropriate detector 212, which causes the ODLU2
0 is automatically stopped and will not be restarted unless the above defects are corrected. Therefore, the light emitter 208 and the detector 212
Can be referred to as a cutoff path sensor. Because these emitters 208 and detectors 212 are
This is because it provides a means for detecting that the path for the picker assembly 48 between the selected locations therein is blocked by the cartridge 38. This is effective in minimizing damage to the cartridge and picker.

A simple means for limiting the field of view of the photosensors and detectors will now be described with reference to FIGS. 10, 11 and 12. The limited field of view improves alignment accuracy and limits the potential for interference between sensor systems. For example, FIG. 10 is a cross-sectional view through the module 36 along the line between two adjacent sensor holes 42 (see FIGS. 3 and 4). Each hole 42, 42A, 42B
Is open to the cylindrical recess 220, and the end of the recess 220 is a mirror 222. The mirror 222 is for reflecting the optical signal emitted by the optical sensor 185 of the picker unit 48 as it moves through the holes 42, 42A, 42B. The reflected optical signal is returned to the optical sensor 185 and detected by the optical sensor 185. In the recess 220, the sensor 185 has holes 42, 42A, 4
When correctly aligned with 2B, the signal will be in holes 42, 42A, 4
Ensure that it is only fed into 2B and returned from the hole.

Referring to FIG. 11, the detector 212 includes
It will be appreciated that placing a detector element 213 at the base of the elongated cylinder 211 provides a limited field of view. Similarly, by providing the light emitting element 209 at the base of the cylindrical body 207 (see FIG. 12), the light emitter 208 can provide a limited field-of-emission. This configuration of emitter and detector ensures that the light from emitter 208 is not reflected from, for example, components within ODLU 20 to find a path around the block to detector 212. . Having described the structural details of the ODLU 20 and the alignment components, a brief description of the control electronics will be provided before describing the example of unit calibration, alignment and operation.

Referring to FIG. 13, the control electronics of ODLU 20 are shown in a block diagram. A controller 250 is located in the center of the control electronics. The controller 250 excludes the data read from the drive 44 or the data write to the drive 44.
Controls all zero data traffic. FIG. 13 shows the first drive 252 and the second drive 254 of the first drive pair. In FIG. 13, the nth drive 256 and the n + 1th drive 2 of another drive pair are shown.
58 is also shown (where n is 4, 6, 8 or 10).
Good). The data from these drives is SCSI
(Small computer system interface, Small
The host computer 262 is directly connected to the host computer 262 along the link 260 of the Computor System Interface.
(Eg, the central computer of the data retrieval and recording system).

The host computer 262 uses the ODLU2
0 requests, 26 links to computer 250
4 and RS232 serial interface. Information about which slot position of the ODLU 20 holds a specific subject matter is stored in the host computer 262. ODLU2
The 0 only knows which slot position cartridge is stored. If these positions change as a result of actuation of ODLU 20, these positions are relayed back to the host computer 262 by the controller. The commands are also transferred via the controller 250 from the operational status displayed on the keypad input device 270 and the 32-character display 272. The keypad input device 270 and the 32-character display 272 will be described later.

The ODLU computer 266 is composed of a 16-bit microprocessor (for example, 80286 microprocessor). Computer 266 is used to calculate the drive's position map, storage of slots and cartridges, and the preferred operating sequence for moving the cartridge between selected positions within ODLU 20.
These calculations are translated by computer 266 into a set of drive commands that are in turn communicated to controller 250 along with the sequence and profile of actuation. The preferred actuation profile is some actuation performed simultaneously such as X and Y axis motion and Z axis rotation of the picker assembly 48. The DP500 controller 250 includes optical and mechanical alignment sensors (collectively designated by numeral 274), a motor limit sensor (collectively designated by numeral 276), a cutoff path sensor (collectively designated by numeral 278). ), And input data from the components of the ODLU 20 consisting of the mailbox 100. The DP500 controller 250 communicates the output command to the X drive servomotor 80, the Y drive servomotor 94, and the (rotating) Z drive servomotor 60. These output commands are communicated via servo amplifiers 284, 286, 288 and servo motor controller 283, respectively, which translates the commands into servo amplifier information. The DP500 controller 250 also communicates commands to the gripper drive stepper motor 190, the gripper solenoid 151 and the mailbox 100.

Next, an example of the interaction between the electronic circuit of FIG. 13 and other components of the ODLU 20 will be described. This example includes a description of the sequence operation for aligning and calibrating the ODLU 20. ODLU
Switching on 20 initiates the complete alignment and calibration sequence. In this sequence, the transfer frame 64 (the picker assembly 4
8) is moved to the left limit of X movement and the lower limit of Y movement (ie, the lower left corner of frame 26, as seen in FIG. 1). This establishes the home reference point. Next, the picker unit 48 is leveled using the sensor 205. Next, move the picker unit 48 in the Y direction (upward).
Drive to. As the picker unit 48 continues to move upward, the optical sensor 185 of the picker assembly 48 (FIG. 2) will
The sensor holes 42 adjacent to the slots 34 are sequentially positioned. When each sensor hole is positioned, the encoder count of the Y drive servomotor 94 is calculated by the computer 266.
Tabulated in the memory, which establishes the slot position.

If the sensor hole is not found at the 25th slot position (ie, the previous 25th slot position based on the spacing of previously positioned slots), the computer 266 causes the picker assembly 48 to move. The upward movement is instructed to search for the sensor hole at the 30th slot position (that is, a position ½ above the space corresponding to the central module 36 of the column). If the thirtieth slot is not found, computer 266
Instruct the picker assembly 48 to continue moving upwards to search for drives. When the sensor hole 42A appears within the space of the central module, the computer 266 notices that the drive is located within the space and establishes and tabulates the position of the drive. Computer 266 then instructs picker 48 to search for sensor hole 42B. Upon encountering sensor hole 42B, computer 266 determines the type of drive (ie, brand) it encountered by examining a table in memory with information about the number and relative position of holes 42B. Since each disk drive can have up to four holes 42B, up to 16 different drive loading and unloading conditions can be stored in the memory of computer 266. The type or brand of disk drive is important because the relative position of the access slot 46 varies with different drive standards.

Next, the picker assembly 48 is driven downwards to search the second drive. Located in the space of the central module, computer 266 notes the presence of the second drive and tabulates its location. Computer 266 then directs picker 48 to search hole 42B to determine the drive type. Once the drive has been positioned and the drive type determined, the picker assembly 48 is driven upwards and slot position calibration is complete. Once the picker unit 48 reaches the upper Y-limit, both photosensors 185 of the picker assembly 48 occupy a position located between the boundary regions 40 of the module 36 (ie the open regions of the slots 34). The solid 48 is rotated by a predetermined amount. In this position, one sensor is located above the other sensor by a certain height. Next, the picker assembly 48
Are driven downward in the Y direction to the previously determined slot position. When sensor 185 receives a signal, which is interpreted as indicating that the cartridge is in a slot, the location of that slot is entered into memory. While the picker assembly 48 is in the upper position of column A, the uppermost sensor 185 is read to position the cartridge. The lower sensor is read as the cartridge moves through the center of the column and into the lower region of the column. Where computer 266 is drive 44
Already knows where is located, so drive 44
Does not mistake the cartridge containing the slot.

When the bay or column 32A is calibrated, the picker unit 48 returns to the lower Y limit. Next, the transfer frame 64 is attached to the sensor arm 20.
0 (see FIG. 2) and the transfer frame 64 is moved in the X direction until it contacts the optical slot sensor 204. next,
A second reference point is established that indicates the center of column 32B. The above procedure is repeated for each bay or column 32A-32E until the location of each slot, drive and cartridge is tabulated or mapped into the non-volatile memory of computer 266. After the calibration sequence, the picker assembly 48 is returned and leveled to the approximate center position of the rack 21 (ie, the position closest to any position on the rack 21). This has also been determined to be a convenient rest position for the picker unit 48 when the picker unit 48 receives no commands. If you don't receive any command for 30 seconds,
The picker assembly 48 is automatically returned to this rest position.

Once all slot 34 and cartridge 38 locations and optical disk drive 44 locations and types have been tabulated and mapped into the memory of the central computer 266, the ODLU 20 will update the ODLU2.
It is now ready to receive a request to move a cartridge within 0. While the ODLU 20 is operating, the drive slots and cartridge table in the computer's memory are continuously updated based on the operation performed. The slot, drive and cartridge maps are stored in non-volatile memory so that the maps are maintained in computer 266 even when ODLU 20 is switched off. Therefore, if the position of the slot, drive or cartridge is not changed while the ODLU 20 is switched off, then the next calibration of the ODLU 20 does not require a complete calibration sequence.

Another useful feature of the dual alignment system is that the optical alignment system is, in some cases, used as a cross check or backup of the mechanical alignment system. For example, FIG. 1 and FIG.
As shown in FIG. 7, when the transfer unit is distorted by an unexpected impact, the mechanical sensor 205 causes the picker assembly 4 to move.
Establish 8 "level" states (this is not the actual level). In this condition, picker assembly 48 is not aligned with slot 34. When the picker unit 48 is driven upward in a mismatched state, the picker unit 48
The upper photosensor 185 no longer matches the photosensor pair 42. This condition is reported as an error condition and this report is displayed on the display 320 (see FIG. 2) or sent as an error message to the computer 266. The picker unit 48 is then rotated until the optical sensor 185 is aligned with the pair of sensor devices 42 (ie, an optically aligned condition is established). Then the drive motor encoder counts corresponding to optically matched level states are mapped into the computer's memory,
Used to level picker unit 48 until damage is repaired.

Next, another important feature regarding the reliability of the ODLU 20 will be described. As mentioned above, the efficiency of an optical disc library unit is determined by the time it takes to find and retrieve a cartridge and place the cartridge in the drive. Therefore, the controller 2
When 50 receives a request to move a cartridge between selected positions, the request is relayed to computer 266 for interpretation. Computer 266 then takes into account a number of important factors in producing the preferred actuation sequence. These factors include, but are not limited to, the distance between selected locations. The drive is already occupied and must be emptied. In this direction (the A side or B side is up) the cartridge occupies the drive and in this direction the cartridge should be inserted into the drive (the cartridge usually faces the A side). Stored upward in slot 34).

One apparently simple request to move the cartridge is a set of actuations or actuation profiles including some actuations of the picker and gripper and one or more actuations of the double picker assembly. . Some of the actuations are simultaneous, others are sequential with variable time intervals between the actuations. Since two pickers and at least two drives are available for actuation, the same objective result is achieved with more than one actuation set. In general, working sets achieved in the shortest time are preferred, but reliability should also be taken into account. From all the operations required to complete a given request, computer 266 requests in the shortest time by performing certain operations simultaneously and executing the request with one or more combinations of components. Determine the sequence of operations (commands) that satisfy.
Therefore, the determination of the shortest time addresses the search speed issue of the optical data disk library unit. Reliable issues are addressed as follows.

The most sensitive components of the optical data disk library unit to wear are the optical disk drive and picker. Thus, the computer 266 of the ODLU 20 is maintained in non-volatile memory, record or count of all (cumulative) operations performed by each drive and picker currently provided therein. This usage count of the drive or picker contributes to the determination of a set of actuations or actuation profiles that move the cartridge between selected positions. In determining the actuation sequence, computer 266 attempts to use all drives of ODLU 20 and each of both pickers to undergo approximately equal wear. For example, with a simple algorithm, the computer 266 may accumulate one working set to be achieved in the shortest time or drive and picker to be used.
d)) and other working sets. Comparing both sets of times, the use-based sequence is executed if the use-based set is executed at the same time, or at least within some predetermined and acceptable long time.

However, the above example is only one method that satisfies the conditions of speed and reliability of the ODLU 20.
It will be apparent to those skilled in the art that several alternative algorithms are possible to implement the above actuation decisions that optimize actuation speed and reduce part wear. The decision to give priority can be modified based on the speed and reliability requirements of a particular user. In normal use, the ODLU 20 is activated by requests and commands from the host computer 262, which is typically located away from where the ODLU 20 is located. However, for example, when realignment and recalibration are performed, or when cartridges are added, ejected, or reordered, the ODLU2 is arranged at the place where the ODLU20 is arranged.
It is often necessary to activate 0. To facilitate operation, the side panel 28 of ODLU 20 (see FIG. 2) is provided with a keypad 300 for entering commands. A 32-character display 320 is provided for monitoring the operation of the ODLU 20, more specifically for confirming the commands and monitoring the responses to these commands.

The layout of the keypad 300 is shown in FIG. The keypad 300 has 24 keys. Of these, ten keys 302 are numeric keys and have the normal function of such numeric keys. The remaining keys are function keys for starting various functions. For example, when the key 304 and the number keys are operated in combination, calibration and alignment are started, and when the key 306 is operated, the operation of the mailbox is started and the numbers are operated. Operating key 308 in combination with key 302 allows the selection of any of the up to 10 built-in optical disk drives. The details of the 32-character display 320 are shown in FIG. The display 320 is formed by a linear array of four 8-character light emitting diode (LED) units. The first group of 17 characters 322 is used to display status information, such as "INIT" (used to initiate a calibration operation) or selected function such as cartridge source or destination number.

The eighteenth character 333 is the ODLU20
Shows a single letter or symbol indicating the operating mode of the. 10
The second group 324 of characters is ODLU20.
It is used to indicate the numbers of the drives located in and the status of these drives. The underlined letter indicates that the drive is located and the letter indicates that the cartridge is in the drive and which side of the cartridge is facing up. For example, as shown in FIG. 15, the information of the segments 328 and 330 indicates that two drives are arranged in the column A, and
The drive (letter 328) indicates that it contains a cartridge (side A facing up). A third group of four characters displays picker actuation. For example,
The segment 332 has an arrow indicating the moving direction of the picker assembly 48. The letters 334, 336 have the symbol "T" representing a picker. The symbol "T" moves up (or down) to indicate that the picker is moving toward (or away from) the slot or drive, and is illuminated solid when the picker contains a cartridge. . Character 334 is picker assembly unit 4
It has a line symbol indicating the eight directions (orientations). When this line is above segment 334 as shown in FIG. 15, the first picker is above and the line is segment 33.
When in the lower part of 4, the second picker is above.
In this regard, although pickers 49 have been described as being physically identical, it should be noted that pickers should be numbered operationally.

In general, the display 320 has an ODLU2
Provides a continuous visual display of 0 current actuations. Another useful feature of ODLU 20 is that it has automatic error recovery capability. This capability is done in part using a stepper motor that drives the gripper. As mentioned above, the advantage of using a stepper motor to drive the gripper is that if the stepper motor encounters excessive resistance, it will slip rather than overcome this resistance. Therefore, the user may issue a command to insert the cartridge into the slot disk of the cartridge or drive into the device 51.
The stepper motor 1 when it encounters a resistance that prevents it from completing the cartridge insertion operation as it receives from the ODLU 20.
90 slips and eventually stops. This error condition is detected and reported to computer 266 as a malfunction. At this point, the automatic error recovery sequence can begin.

In one example of an automatic error recovery sequence, when an error condition is detected, the activated picker and grabber is reset to the predominant condition prior to the faulty operation attempted, and then the operation is retried. To be done. When an error is detected again, both pickers are reset, the picker assembly is releveled, and the second run is retried. When the error is reported again, the X and Y axis drive motors 80 are recalibrated respectively.
Then, the third operation is tried. If the operation cannot be completed in this third attempt, the cartridge is returned to its original position and a signal is sent to the user that the operation cannot be completed. The optical data disc library unit having some useful features has been described above. An advantageous feature of the invention is the provision of a double picker unit with two pickers assembled back to back. Each picker has a gripping device. Each gripping device is driven by a stepper motor, which is operable at a programmable variable speed to match the loading and unloading forces of the system's optical disk drive. The unit of the present invention has a dual alignment system with both optical and mechanical sensors. The dual picker assembly optical sensor is used to detect and correct erroneous alignments due to picker assembly mechanical sensors. The drive motor (s) are arranged to move the picker assembly in the X and Y directions while the picker assembly is rotated. The operation of the unit is programmed to complete the operation in the shortest possible time, or equal wear of the picker and drive.

The invention has been described with reference to its preferred and alternative embodiments. However, the invention is not limited to the embodiments shown and described, but the scope of the invention is defined by the claims.

[Brief description of drawings]

FIG. 1 is a front view schematically showing an optical data disc library unit of the present invention.

FIG. 2 is a schematic side sectional view taken along line 2-2 of FIG.

FIG. 3 is a schematic view of a slot module holding an optical data disk cartridge.

FIG. 4 is a schematic diagram of an optical disk drive including a cartridge retainer mechanism and a replacement bezel.

FIG. 5 is a schematic side view of the double picker assembly of the present invention showing a flat actuator used to actuate the cartridge retainer mechanism.

FIG. 6 is a plan view of the picker assembly of FIG. 5, showing a gripping mechanism, a flat actuator for actuating a cartridge retainer mechanism, and a gripping device drive mechanism according to the present invention.

7 is a schematic end view taken along the line 7-7 of FIG. 6, showing a stepper motor of the picker drive mechanism.

8 is a part of the plan view of FIG. 6, with the gripping device omitted to show details of the gripping device drive mechanism.

FIG. 9 is a schematic diagram showing a configuration of an optical sensor, a mechanical sensor, and an optical detector of the library unit of FIG.

FIG. 10 is a schematic view showing details of an embodiment of a visual field limiting device of an optical sensor.

11 is a schematic view showing an embodiment of the visual field limiting device for the photodetector in the configuration of FIG.

12 is a schematic view showing a visual field limiting device for a light emitter in the configuration of FIG. 9. FIG.

13 is a block diagram illustrating a layout of command and control electronics of the library unit of FIG.

14 is a schematic diagram showing a keypad for inputting commands to the library unit of FIG. 1. FIG.

15 is a schematic diagram showing a 32-character display for monitoring the operation of the library unit of FIG.

FIG. 16 is a perspective view showing an optical disk drive including a cartridge retainer mechanism, a cartridge held by the retainer mechanism, a flat actuator for operating the cartridge retainer mechanism, and a gripping device used for ejecting the cartridge.

FIG. 17 is a schematic side view of a cartridge retainer mechanism, a cartridge held by the retainer mechanism, a gripping mechanism used to take out the cartridge, and a flat actuator that operates the cartridge retainer mechanism.

FIG. 18 is a schematic side view of a cartridge retainer mechanism, a cartridge held by the retainer mechanism, a gripping mechanism used to take out the cartridge, and a flat actuator that operates the cartridge retainer mechanism.

Front Page Continuation (72) Inventor Jeffrey H. Lee United States California 94087 Sunnyvale Mallard Way 1509 (72) Inventor David A. Minor United States California 94536 Fremont Bonnie Way 38882 (72) Inventor Ralph F. Manniqueys United States California 95070 Saratoga Manor Drive 20512

Claims (16)

[Claims] 1. A rack means having a plurality of generally parallel spaced storage slots, each slot having a shape for storing one optical data disk cartridge, at least a first And a second optical disc drive, each optical disc drive having an access slot for inserting and removing a cartridge, the optical disc drive comprising: Means for removing the cartridges from the optical disc drive, mounted adjacent to each other in the rack with a space between them, and means for removing the cartridges in the access slots of the drive after the cartridges have been removed from the optical disc drive. Means for releasably holding a part of the rack, Having first and second pickers for transporting the cartridge between selected positions, the pickers being assembled together in a back-to-back relationship, each picker inserting the cartridge into a slot And holding means for holding the cartridge in a releasable manner, each holding means having a holding means for releasably holding the cartridge, and a driving means for driving the picker in the X direction. A first motor that moves the picker in a Y direction that is perpendicular to the X direction, a third motor that rotates the picker around a Z axis that is perpendicular to the X axis and the Y axis. Two stepper motors, each stepper motor being coupled to each gripping device for moving the gripping device in the direction of the Z-axis; Further comprising a solenoid, each solenoid being coupled to each holding means for actuating said holding means, controller means for communicating drive commands to said motor, and mapping of cartridge positions in said slots, drives and racks. And a mechanical alignment means for determining each position of a plurality of fixed reference points, the alignment means for detecting the position of each slot and the position of each drive, and accommodating the cartridge. Optical alignment means for determining the position of each of the slots, the means for storing a map including the positions of the slot, drive, cartridge accommodating slot and reference point, and updating the map after the cartridge is moved. To determine the operating profile and Serial further comprises a means for determining a driving command device stores a plurality of optical disk cartridge characterized in that it comprises a path of the picker between a position where the actuating profile is selected. 2. The apparatus of claim 1, wherein the pickers are moved and rotated at the same time. 3. The apparatus according to claim 2, further comprising optical sensor means for determining whether the path is blocked. 4. The operating profile determining means comprises means for determining a count of operations performed by each drive and selecting a drive to use based on the count. The device according to. 5. The operation profile determining means comprises means for determining a count of operations performed by each of the pickers and selecting a picker to use based on the count. The described device. 6. The apparatus according to claim 1, wherein the slots are arranged in a plurality of columns. 7. The apparatus of claim 6, wherein at least one of said columns is formed of a plurality of separable modules, each module comprising at least two slots. 8. The optical disc drive includes a side casing, the gripping device includes a key that engages a slot in the cartridge, and the key is crushably attached to the gripping device. The apparatus of claim 1, wherein the key is crushed when engaged with a side casing of the optical disc drive. 9. The apparatus of claim 1, wherein the map further comprises loading and unloading characteristics of each of the optical disc drives mounted on the rack means. 10. A rack means having storage slots generally parallel and spaced apart, each slot having a shape for storing one optical data disk cartridge, at least first and first. Two optical disc drives, each of which has an access slot for inserting and removing a cartridge, wherein the optical disc drives are generally parallel and spaced apart. Spaced apart and adjacent to each other in the rack and having first and second pickers for transferring cartridges between selected positions of the rack, the pickers being integral in a back-to-back relationship Each of the pickers has a gripping device for inserting the cartridge into the slot and removing the cartridge from the slot. Each of the gripping devices is provided with a holding means for holding the cartridge in a releasable manner, and has a motor driving means, the driving means having a first motor for moving the picker in the X direction, and A second motor for moving the picker in a Y direction perpendicular to the X direction; a third motor for rotating the picker around a Z axis perpendicular to the X axis and the Y axis; and two stepper motors. Each stepper motor is coupled to each gripping device to move the gripping device in the direction of the Z-axis, and further comprises two solenoids, each solenoid for actuating the holding means. Controller means connected to holding means for communicating drive commands to the motor and mapping of cartridge positions in the slots, drives and racks. And a mechanical alignment means for determining each position of a plurality of fixed reference points, the alignment means for detecting the position of each slot and the position of each drive, and accommodating the cartridge. Optical alignment means for determining the position of each of the slots, the means for storing a map including the positions of the slot, drive, cartridge accommodating slot and reference point, and updating the map after the cartridge is moved. Means for determining an actuation profile, and means for determining the drive command therefrom, wherein the actuation profile comprises a path of the picker between selected positions. A device for storing multiple optical disc cartridges. 11. The apparatus of claim 10, wherein the pickers are moved and rotated at the same time. 12. The apparatus of claim 11, further comprising photosensor means for determining whether the path is blocked. 13. The operating profile determining means comprises means for determining a count of operations performed by each drive and selecting a drive to use based on the count. The device according to. 14. The operation profile determining means comprises means for determining a count of operations performed by each of the pickers and selecting a picker to use based on the count. The described device. 15. The apparatus of claim 10, wherein the slots are arranged in multiple columns. 16. The apparatus of claim 15, wherein at least one of the columns is formed of a plurality of separable modules, each module having at least two slots.