JP2972594B2 - Collective magnetic tape unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collective type in which a large number of magnetic tape cartridges are accommodated, a designated magnetic tape cartridge is taken out of the cartridge by an instruction from a host device, and information is recorded or reproduced on the magnetic tape cartridge. The present invention relates to a magnetic tape device.

[0002]

2. Description of the Related Art FIG. 3 is a perspective view showing an external appearance of an example of a conventional collective magnetic tape device, FIG. 4 is a plan view of the accessor of FIG. 3 and its periphery, and FIG. 5 is a positioning sensor of FIG. (A) is a front view, FIG.
(B) is a perspective view.

[0003] A medium of a conventional collective type magnetic tape device which accommodates a number of magnetic tape cartridges (mediums), takes out a specified magnetic tape cartridge from the host device according to a command from a higher-level device, and records or reproduces information therefrom. As shown in FIG. 3, the transfer mechanism unit includes a cartridge storage unit 1 in which a plurality of cells accommodating a medium are regularly arranged vertically and horizontally, and a medium from a designated cell of the cartridge storage unit 1. An accessor 2 for taking out, holding, moving to a recording / reproducing unit (not shown), taking out the medium from the recording / reproducing unit, holding, and moving it to a designated cell.

[0004] As shown in FIGS. 4 and 5, the accessor 2 is connected to a drive motor 4 by a timing belt 3, and the rotation speed and rotation angle of the drive motor 4 are detected by a tacho encoder 5. To stop the accessor 2 at the position corresponding to the designated cell in the cartridge storage unit 1, each cell is assigned a unique address, and the accessor 2 is located at a position corresponding to a middle position between adjacent cells. A positioning flag 6 having a notch (cell edge) is provided, the cell edge is detected by a positioning sensor 7, and counting of the output pulse of the tacho encoder 5 is started from the time when the cell edge is detected by the positioning sensor 7, and a pulse designated in advance Positioning is performed using the numbered positions as target positions.

[0005] The conventional collective magnetic tape apparatus constructed as described above has a problem in that the accessor drive system from the drive motor 4 to the timing belt 3, from the timing belt 3 to the accessor 2, and from the accessor 2 to the positioning flag 6 is deformed by a spring. The detected position of the cell edge is shifted by an amount corresponding to the spring deformation, and even if the accessor 2 is stopped at a position where the count value of the output pulse of the tacho encoder 5 reaches a predetermined number of pulses, the correct position is obtained. At a position corresponding to the spring deformation.

[0006]

As described above, in the conventional collective magnetic tape device, the detected position of the cell edge is shifted by an amount corresponding to the spring deformation due to the spring deformation of the accessor drive system. Even if the accessor is stopped at a position where the count value of the output pulse of the tacho encoder has reached a predetermined number of pulses, the accessor is stopped at a position corresponding to spring deformation from a correct position. ing.

To reduce the amount of the spring deformation, it is necessary to increase the rigidity of the accessor drive system.
For this purpose, it is necessary to use a tough material or strengthen the structure, and furthermore, the weight is increased and the drive motor and its power supply must be increased, resulting in cost reduction. Another problem arises that up is inevitable.

An object of the present invention is to provide a collective magnetic tape device which can solve the above-mentioned drawbacks of the conventional collective magnetic tape device and can improve the positioning accuracy of the accessor with a minimum increase in cost. is there.

[0009]

According to the present invention, there is provided a collective magnetic tape apparatus comprising: a cartridge storage section in which a plurality of cells accommodating a magnetic tape cartridge are regularly arranged in a vertical direction and a horizontal direction; A timing belt for transmitting the power of the drive motor; and a tacho encoder for detecting a rotation speed and a rotation angle of the drive motor. An accessor for moving the magnetic tape cartridge to the recording / reproducing unit, taking out the magnetic tape cartridge from the recording / reproducing unit, holding and moving the magnetic tape cartridge to a designated cell, at a position corresponding to an intermediate position between adjacent cells. A positioning flag having a notch is provided, and the accessor is provided with the positioning flag. A position sensor that starts counting the output pulses of the tacho encoder from the time when the notch is detected by the positioning sensor, and sets a position at which a predetermined number of pulses is reached as a target stop position as the target stop position. In the collective magnetic tape device for performing the positioning of the above, a stiffness measurement flag having a hole having an interval equal to the pitch interval of the cells is provided outside and adjacent to the positioning flag, and the stiffness corresponding to the stiffness measurement flag is provided in the accessor. A measurement sensor is provided, an interval between output pulse signals of the stiffness measurement sensor that is output from when the drive motor is started to when the accessor reaches a target speed is measured, and a reciprocal of the measured value is calculated. The change in the speed of the accessor is obtained by By calculating the overshoot amount of the accessor, the spring constant of the entire accessor drive system is estimated, and the deviation obtained from the product of the estimated value of the spring constant of the entire accessor drive system and the deceleration torque is calculated by calculation prior to deceleration. Thus, the target stop position is corrected in advance.

That is, a collective magnetic tape apparatus according to the present invention comprises: a cartridge storage section in which a plurality of cells accommodating a magnetic tape cartridge are regularly arranged in the up-down direction and the left-right direction; And a tacho encoder for detecting a rotation speed and a rotation angle of the drive motor, and taking out and holding the magnetic tape cartridge from a designated cell of the cartridge storage unit to hold the magnetic tape cartridge. An accessor for moving the magnetic tape cartridge from the recording / reproducing unit to the recording / reproducing unit, holding the magnetic tape cartridge, and moving the cartridge to a designated cell, and having a notch at a position corresponding to an intermediate position between adjacent cells. A positioning flag is provided, and the notch of the positioning flag is provided in the accessor. A positioning sensor for detecting the notch is detected by the positioning sensor, and the output pulse of the tacho encoder is counted from the time when the notch is detected. And a stiffness measurement flag having a hole adjacent to the positioning flag and having an interval equal to the pitch of the cells, and provided at a position corresponding to the stiffness measurement flag of the accessor. A stiffness measurement sensor, a measurement counter circuit that measures an interval between pulse signals output from the stiffness measurement sensor after the drive motor is started until the accessor reaches a target speed, and a value of the counter circuit. From the obtained speed response characteristic of the rigidity measuring sensor, the entire drive system of the accessor is obtained. A logical operation unit that calculates the spring constant of the accessor, and estimates the amount of deformation of the accessor at the time when the notch is detected based on the spring constant calculated by the logical operation unit to correct the target stop position. It was done.

[0011]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a view showing a stiffness measuring sensor and a stiffness measuring flag according to an embodiment of the present invention.
2B is a perspective view, and FIG. 2 is a characteristic diagram showing an output signal of the rigidity measurement sensor of FIG.

The present embodiment has almost the same configuration as the conventional collective magnetic tape device shown in FIGS.
The only difference is that a stiffness measurement flag provided adjacent to the positioning flag and a stiffness measurement sensor provided on the accessor corresponding to the stiffness measurement flag are provided. Therefore, the following description will be made mainly for the rigidity measurement flag and the rigidity measurement sensor.

As shown in FIG. 1A, the rigidity measurement flag 18 is adjacent to and outside the positioning flag 16 (which is the same as the positioning flag 6 in FIGS. 3 to 5) (the main body of the accessor 12). (The farthest position from the camera). As shown in FIG. 1B, the rigidity measurement flag 18
Has a plurality of holes 18a having an interval equal to the pitch interval of the cells of the cartridge storage section 1, and the interval is set to be sufficiently shorter than the acceleration period of the drive motor 4 of the accessor 2. . The positioning flag 16 and the rigidity measurement flag 18 are formed by performing notch processing or etching processing on a sheet metal material.

The accessor 12 has a positioning flag 16
A positioning sensor 17 (same as the positioning sensor 7 in FIGS. 3 to 5) and a stiffness measurement sensor 19 are provided corresponding to the stiffness measurement flag 18. The stiffness measurement sensor 19 is configured to sandwich the stiffness measurement flag 18 between the light emitting element and the light receiving element, and has a pulse shape that changes when the stiffness measurement flag 18 blocks light emitted by the light emitting element and transmits light. Generates a signal.

The output signal of the stiffness measuring sensor 19 is a pulse-like signal that repeats on-off until the drive motor 4 is activated and the accessor 2 reaches the target speed, and the pulse interval is measured. For this purpose, a sufficiently fast clock pulse is used.

When the interval between the output pulse signals of the stiffness measuring sensor 19 is measured and its reciprocal is obtained by calculation, the value indicates the actual speed change of the portion of the accessor 2 corresponding to the positioning sensor 17 during acceleration. I have.

The drive motor 4 is driven by a constant current drive circuit to generate a constant acceleration torque.

FIG. 2 is a characteristic diagram showing the acceleration characteristic of the accessor drive system obtained from the output signal of the rigidity measuring sensor of FIG.
The acceleration characteristic 21 of the actual accessor drive system and the acceleration characteristic 22 when the accessor drive system is a rigid body are shown side by side.

Here, assuming that the damping characteristic of the accessor drive system is adjusted to be constant independently of the device, the overshoot of the acceleration characteristic 21 increases as the spring constant of the entire accessor drive system increases. Become smaller.
Therefore, the spring constant of the entire accessor drive system can be estimated by measuring the overshoot amount. Using this principle, the spring constant of the entire accessor drive system for each device is estimated by measuring the amount of overshoot when accelerating the accessor.

When the accessor is approaching the target stop position and decelerating at a constant acceleration, the rotation angle of the drive motor 4 is multiplied by the deceleration torque multiplied by the spring constant of the entire accessor drive system measured during acceleration. (Measured by the tacho encoder 5) and the actual position of the positioning sensor 17 deviates.

By calculating this deviation amount by calculation prior to deceleration and correcting the target stop position in advance thereby, the positioning accuracy of the stop position of the accessor can be improved.

[0023]

As described above, the collective magnetic tape device of the present invention is provided with a stiffness measuring flag having holes adjacent to the positioning flag and having an interval equal to the cell pitch interval outside the positioning flag. By measuring the interval of the output pulse signal of the stiffness measurement sensor that is output from when the drive motor is started until the accessor reaches the target speed, the change in the speed of the accessor is calculated by calculating the reciprocal of the measured value. The spring constant of the entire accessor drive system is estimated by calculating the overshoot amount of the accessor from the speed change of the accessor, and the deviation amount obtained from the product of the estimated value of the spring constant of the entire accessor drive system and the deceleration torque Is calculated prior to deceleration, and the target stop position is thereby corrected in advance. , There is an effect that it becomes possible to improve the positioning accuracy of the accessor stop position to minimize the cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing a stiffness measuring sensor and a stiffness measuring flag according to an embodiment of the present invention, wherein (a) is a front view and (b) is a perspective view.

FIG. 2 is a characteristic diagram showing an output signal of the rigidity measurement sensor of FIG.

FIG. 3 is a perspective view showing an external appearance of an example of a conventional collective magnetic tape device.

FIG. 4 is a plan view of the accessor of the example of FIG. 3 and its periphery.

5A and 5B are diagrams showing a positioning sensor and a positioning flag of the example of FIG. 3, wherein FIG. 5A is a front view and FIG. 5B is a perspective view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cartridge storage part 2 ・ 12 Accessor 3 Timing belt 4 Drive motor 5 Tach encoder 6 ・ 16 Positioning flag 7.17 Positioning sensor 18 Rigidity measuring flag 18a Hole 19 Rigidity measuring sensor 21 Acceleration characteristics of accessor driving system 22 Accessor driving system is rigid Acceleration characteristics in case of

Claims (2)

(57) [Claims] 1. A cartridge storage section in which a plurality of cells accommodating a magnetic tape cartridge are regularly arranged in a vertical direction and a horizontal direction, a drive motor, a timing belt for transmitting power of the drive motor, and a drive belt of the drive motor. A tacho encoder for detecting a rotation speed and a rotation angle, taking out and holding the magnetic tape cartridge from a designated cell of the cartridge storage unit, moving the magnetic tape cartridge to a recording / reproducing unit, and An accessor for taking out the magnetic tape cartridge from the cartridge, holding the magnetic tape cartridge and moving the cartridge to a designated cell, providing a positioning flag having a notch at a position corresponding to an intermediate position between the adjacent cells, and providing the accessor with the positioning flag. A positioning sensor for detecting the notch of the flag; A collective magnetic tape device that starts counting output pulses of the tacho encoder from the time when the notch is detected by a sensor and positions the accessor as a target stop position at a position where the number of pulses has been specified in advance. A stiffness measurement flag having a hole having an interval equal to the pitch interval of the cells is provided outside and adjacent to the positioning flag, a stiffness measurement sensor corresponding to the stiffness measurement flag is provided in the accessor, and the drive motor is started. Measure the interval of the output pulse signal of the stiffness measurement sensor that is output until after the accessor reaches the target speed,
The reciprocal of the measured value is calculated to determine the speed change of the accessor, and the overshoot amount of the accessor is determined from the speed change of the accessor to estimate the spring constant of the entire accessor drive system. A collective magnetic tape device, wherein a shift amount obtained from a product of an estimated value of the entire spring constant and a deceleration torque is obtained by calculation prior to deceleration, and the target stop position is corrected in advance by the calculation. 2. A cartridge storage unit in which a plurality of cells accommodating a magnetic tape cartridge are regularly arranged in a vertical direction and a horizontal direction, a drive motor, a timing belt for transmitting power of the drive motor, and a drive unit of the drive motor. A tacho encoder for detecting a rotation speed and a rotation angle, taking out and holding the magnetic tape cartridge from a designated cell of the cartridge storage unit, moving the magnetic tape cartridge to a recording / reproducing unit, and An accessor for taking out the magnetic tape cartridge from the cartridge, holding the magnetic tape cartridge and moving the cartridge to a designated cell, providing a positioning flag having a notch at a position corresponding to an intermediate position between the adjacent cells, and providing the accessor with the positioning flag. A positioning sensor for detecting the notch of the flag; A collective magnetic tape device that starts counting the output pulses of the tach encoder from the time when the notch is detected by a sensor and positions the accessor as a target stop position at a position where the number of pulses has been specified in advance, A stiffness measurement flag having a hole adjacent to the positioning flag and having an interval equal to the pitch interval of the cell outside thereof,
A stiffness measurement sensor provided at a position corresponding to the stiffness measurement flag of the accessor, and an interval between pulse signals output from the stiffness measurement sensor after the drive motor is started and before the accessor reaches a target speed. And a logic operation unit for calculating a spring constant of the entire drive system of the accessor from a speed response characteristic of the stiffness measurement sensor obtained by a value of the counter circuit, wherein the logic operation unit calculates A set-type magnetic tape device for estimating an amount of deformation of the accessor at a time point when the notch is detected based on the spring constant and correcting the target stop position.