JPH0476851A - Position deviation correcting system - Google Patents

Abstract

PURPOSE:To exactly grasp a position deviating amount and to accurately correct it by controlling the drive of a motor so that the position deviation amount can be within a prescribed stop position range amount. CONSTITUTION:When a medium conveying mechanism part 11 deviates the position from a stop position by disturbance such as earthquakes, etc., an MPU 16 reads a position data Xn from a counter in a fixed cycle and calculates difference from a stop position data Xm stored in advance so as to calculate a position deviating amount Xl. Next, the position deviating amount Xl is compared with a prescribed position deviation detecting amount and in the case of Xl>=l, a position deviation correcting current imax is set. Then, the position deviating amount Xl is calculated again and it is discriminated whether the position deviating amount Xl is within a stop position range amount L or not. In the case of X<L, a holding current imax is set. Thus, since the position deviation of the medium conveying mechanism part 11 is detected by an encoder 13 fitted to a DC motor 12 and the drive of the DC motor 12 is controlled, the position deviating amount can be exactly grasped and accurately corrected without limiting the sensitivity or position of a sensor as conventional.

Description

[Detailed Description of the Invention] [Summary] Regarding a positional deviation correction method for a medium transport mechanism used in a library device, the present invention aims to provide a positional deviation correction method that can accurately correct positional deviations. a rotation angle detection means that is attached to a motor that moves and presses the mechanism section and generates a pulse at every fixed rotation angle; a counting means that counts the pulses and outputs position data of the medium transport mechanism section; and the position data. and a determining means for determining whether the positional deviation amount is within a predetermined stop position range amount; The motor is configured to be drive-controlled so as to be within a stop position range.

TECHNICAL FIELD The present invention relates to a positional deviation correction method for a medium transport mechanism used in a library device.

For example, a library device is used as an external storage device for a computer system. The basic components of a library device are a recording/playback mechanism for removable storage media, a media storage, and a media transport mechanism, and it stores hundreds to thousands of volumes of media and performs media selection and storage. , the installation and removal of the recording/playback mechanism are automated.

The media transport mechanism unit /'% handles the media and transports the media. The movement of the medium transport mechanism is controlled by a DC motor, and the pressing of the medium to a stop position is controlled.

Therefore, when a positional shift occurs due to a disturbance such as an earthquake, it is necessary to accurately correct this positional shift.

[Prior Art] As a conventional method for correcting positional deviation of a medium transport mechanism section, there is a method as shown in FIG. 4, for example.

In FIG. 4, reference numeral 1 denotes a medium transport mechanism section used in a library apparatus. The medium transport mechanism section 1 has a hand section 3 for handling a medium 2, and is controlled in movement by a motor (not shown) and at a stop position (pushing). The pressing is controlled by the position).

Reference numeral 4 indicates a light emitting diode attached to one printed board 5, and 6 indicates a phototransistor attached to the other printed board 7. Misalignment of the light emitting diode 4 and the phototransistor 6 in the medium transport mechanism section 1 as a whole This constitutes a gap sensor 8 that detects.

If a disturbance such as an earthquake causes a positional shift between the media transport mechanism section 1 and 42 (j! - 10 mm) in the direction indicated by the arrow B, the light emitted by the light emitting tie auto 4 will be transmitted to the media transport mechanism section. 1, the gap sensor 8
is turned on to detect positional deviation.

In this case, as shown in FIG. 5, the positional deviation correction current 11 flows to the DC motor, and the medium transport mechanism section 1 is pulled back to the above-mentioned stop position by driving the DC motor. Then, when the medium transport mechanism section 1 returns to the stop position A and is no longer blocked by light, the gear knob sensor 8 is turned off and the current i
is the normal holding current (the attraction current) is 10.

[Problems to be Solved by the Invention] However, in such a conventional positional deviation correction method, the positional deviation detection position changes depending on the sensitivity of the gap sensor, and the detection position is limited depending on the position of the gap sensor. Therefore, the detection position could not be easily changed, and the accurate stop position and current position could not be determined. As a result, there was a problem in that positional deviation could not be corrected with high accuracy.

The present invention has been made in view of such conventional problems, and it is an object of the present invention to provide a positional deviation correction method that can correct positional deviations with high accuracy.

[Means to solve the problem] FIG. 1 is a diagram explaining the principle of the present invention.

In FIG. 1, reference numeral 13 is a rotation angle detection means that is attached to a motor 12 that moves and presses the medium transport mechanism 11 and generates a pulse at every constant rotation angle; A counting means for outputting position data; 1.6A a calculation means for calculating a positional deviation amount which is the difference between the position data and the stop position data; 16B a calculation means for determining whether the position deviation amount is within a predetermined stop position range amount; This is a means of determining.

When the media transport mechanism moves away from the stop position due to a disturbance such as an earthquake and a position shift occurs, the pulses generated by the rotation angle detection means are counted by the counting means, and the amount of position shift is calculated by the calculation means. calculate.

When the amount of positional deviation exceeds the predetermined position range amount, the motor is drive-controlled to correct the media transport mechanism so that it is within the predetermined position range amount.

That is, in the present invention, the amount of positional deviation can be accurately grasped and corrected with high precision without being limited to the sensitivity or position of the sensor as in the conventional example.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIGS. 2 and 3 are diagrams showing one embodiment of the present invention.

In FIG. 2, Jl is a medium transport mechanism section used in the library apparatus, and the medium transport mechanism section IJ handles and moves the medium.

12 is a DC motor, and the DC motor 12 moves the medium transport mechanism section 11 and controls pressing it to a stop position.

Reference numeral 13 denotes an encoder as rotation angle detection means. The encoder 3 is attached to the DC motor 12 and generates a pulse at every fixed rotation angle.

14 is a counter (tacho counter) as a counting means, and the counter 14 counts the pulses of the encoder 13 and outputs the count value (position data Xn) to the MPU 16 via the input/output control section 15.

The MPU 16 functions as a calculation means 16A that calculates the positional deviation amount Xi which is the difference between the position data Xn and the pre-stored stop position data Xm, and the positional deviation amount Xi is a predetermined positional deviation detected amount! (for example, 1 mm) and the stop position range amount L (for example, 0.5 mm).

Reference numeral 17 denotes a RAM, in which only predetermined positional deviation detection, measurement, and predetermined stop position range amounts are stored in advance.

The MPU 16 calculates the positional deviation amount X1 and the detected positional deviation amount! Position deviation correction current ima from the relationship with the stop position range scale
Set x or holding current (normal attraction is current) imin. That is, the digital signal output from the MPL+16 is converted into an analog signal by the digital-to-analog converter 18, and then amplified by the amplifier 19 and then converted to a DC signal.
The motor 12 is driven and controlled.

Next, the operation will be explained.

FIG. 3 is a flowchart illustrating the invention in detail.

In FIG. 3, first, in step S1, when the medium transport mechanism section 11 is displaced from its stop position due to a disturbance such as an earthquake, the MPU 16 reads position data Xn from the counter 14 at a constant cycle and stores the position data in advance. The difference between the stop position data Xm and the stop position data Xm is calculated to obtain the positional deviation Ill.

Next, in step S2, the positional deviation tXZ is compared with a predetermined detected positional deviation amount (for example, 1 mm), and when xl<1, a holding current i min is set in step S3, and the process returns to step S1. On the other hand, when XL≧1, the positional deviation correction current imax is set in step S4.

Then, in step S5, the positional deviation amount is again X! In search of
In step S6, the positional deviation amount Xi! is the stop position range amount L (
For example, it is determined whether the distance is within 0.5 mm).

X! When ≧L, the positional deviation amount XJ! is maintained while the positional deviation correction current imax is maintained. is determined, and when XZ<L, a holding current i min is set in step S7.

In this way, the positional deviation of the medium transport mechanism section 11 is detected by the encoder 13 attached to the DC motor 12, and the
Since the motor 12 is driven and controlled, the amount of positional deviation can be accurately grasped and corrected with high precision without being limited to the sensitivity and position of the sensor as in the conventional case.

Effects of the Invention a As described above, when a positional shift occurs due to a disturbance such as an earthquake, the amount of positional shift can be accurately grasped and corrected with high precision.

[Brief explanation of drawings]

FIG. 1 is a diagram explaining the principle of the present invention. 2nd rI! J is a diagram showing an embodiment of the present invention, FIG. 3 is a flowchart, FIG. 4 is a diagram showing a conventional example, and FIG. 5 is a diagram showing sensor output and drive current. In the figure, 11... Medium transport mechanism section, 12... Motor (DC motor), 13... Encoder (rotation angle detection means) 14... Counter (counting means), 15... Input/output control Section 16...MPU. 16A...Calculation means 16B...Discrimination means, 17...RAM. 18...D/A converter, 19...amplifier.

Claims (1)

[Claims] a rotation angle detection means (13) that is attached to a motor (12) that moves and presses the medium transport mechanism section (11) and generates a pulse at every constant rotation angle; a calculating means (16A) for calculating a positional deviation amount which is the difference between the positional data and the stop position data; A positional deviation correction method characterized in that the motor (12) is drive-controlled so that the positional deviation amount is within the predetermined stop position range amount.