magnetic tape device

Abstract

Prevents magnetic tape from falling off its path in the event of a power outage. [Solution] The magnetic tape device 10 comprises a set of reel mechanisms 20 and 21 that use an electric motor to feed and rewind the magnetic tape 13, brake mechanisms 30 and 31 that are configured to be able to apply a brake to the reel mechanism that is feeding out the magnetic tape 13, and a control device 40 that activates the brake mechanism for one of the reel mechanisms that is feeding out the magnetic tape 13 when the power supply to the electric motor is stopped.

Description

[Technical Field]

[0001] The present disclosure relates to a magnetic tape device that records and plays back data on a magnetic tape. [Background technology]

[0002] Magnetic tape drives have long been known as a means for storing large amounts of data. A magnetic tape drive continuously records and plays back data by feeding magnetic tape at high speed. A magnetic tape drive is equipped with a magnetic head for writing and reading data, and a structure for pulling and winding the magnetic tape around a reel while bringing the magnetic tape into contact with the magnetic head.

[0003] The configuration of a conventional magnetic tape device will now be described with reference to Figures 8 and 9. Figure 8 is a top view showing the configuration of a conventional magnetic tape device. Figure 9 is a side view showing the configuration of a conventional magnetic tape device.

[0004] As shown in Figures 8 and 9, the magnetic tape device 100 is mainly composed of a tape cartridge 101, a guide roller 105, a reel, a reel motor, a magnetic head 106, and a housing 109. The reel is further composed of a cartridge reel 102 and a device reel 104. The reel motor is composed of a motor 107 that drives the cartridge reel 102 and a motor 108 that drives the device reel 104. In Figure 9, 107A is the shaft of the motor 107, and 107B is a clutch provided on the shaft 107A. 108A is the shaft of the motor 108. Also, in Figures 8 and 9, only the outer edge of the housing 109 is shown.

[0005] The tape cartridge 101 stores the magnetic tape 103 inside by attaching one end of the magnetic tape 103 to a cartridge reel 102 and winding it up. When the tape cartridge 101 is inserted into the magnetic tape device 100, the leading end of the magnetic tape 103 wound around the cartridge reel 102 is pulled out from the tape cartridge 101, and the magnetic tape 103 is then routed along a predetermined path and wound around a device reel 104 inside the magnetic tape device.

[0006] After this state is reached, the magnetic tape 103 can move between the cartridge reel 102 and the drive reel 104 within the magnetic tape device. Regarding the direction of movement of the magnetic tape 103, the direction from the cartridge reel 102 to the drive reel 104 is called the forward direction, and the movement operation is called the forward operation. Also, the direction of movement of the magnetic tape 103 from the drive reel 104 to the cartridge reel 102 is called the reverse direction, and the movement operation is called the reverse operation.

[0007] As described above, the magnetic tape 103 travels along a predetermined path within the magnetic tape device 100, is guided along that path by guide rollers 105, and comes into contact with the magnetic head 106, which reads and writes data. Data is continuously recorded or reproduced by moving the magnetic tape 103 at the same time as the magnetic head 106 reads and writes data. The moving speed of the magnetic tape 103 at this time is kept constant by adjusting the rotation speed of the reel motors, respectively, in order to stabilize recording accuracy.

[0008] The rotation speed of the reel motor is variably controlled according to the amount of magnetic tape 103 wound on the reel. When a large amount of magnetic tape 103 is wound, the diameter is large, so the rotation speed is slowed down, and when a small amount of magnetic tape 103 is wound, the diameter is small, so the rotation speed is increased, so control is performed to keep the moving speed of the magnetic tape 103 constant.

[0009] The forward operation in a conventional magnetic tape device will be described with reference to Figures 10 and 11. Figure 10 is a diagram illustrating the forward operation in a magnetic tape device. Figure 11 is a diagram showing the change in the amount of tape taken up during the forward operation.

[0010] As shown in Figure 10, during forward operation, the magnetic tape 103 moves from the cartridge reel 102 to the device reel 104. In Figure 11, the change in the amount of tape during forward operation is shown divided into the beginning, middle, and end stages. As shown in Figure 11, at the beginning, almost all of the tape is wound on the cartridge reel 102, and there is almost no tape left on the device reel 104. At the middle stage, the cartridge reel 102 and the device reel 104 have the same amount of tape wound on them. At the end stage, most of the magnetic tape 103 has been unwound from the cartridge reel 102 and wound onto the device reel 104.

[0011] Suppose a power outage occurs while the magnetic tape 103 is moving at high speed in the magnetic tape device 100 to read and write data. In this case, if the rotation speeds of the reel motors of the cartridge reel 102 and the device reel 104 are different, there will be a difference in the time it takes for each reel motor to stop. As a result, the magnetic tape 103 will not be properly wound, will hang down under its own weight, and will fall off the specified path. As a result, the magnetic tape 103 that has fallen off the path may come into contact with a surrounding metal frame or uneven parts of the mechanism, and may be damaged. Furthermore, such damage may cause the magnetic tape to break, bend, or tear, which may lead to a decrease in data reproducibility or even loss.

[0012] To prevent the magnetic tape from falling off during such a power outage, a short brake has conventionally been used in magnetic tape devices 100. Here, we will explain short brakes. Normally, even when power is cut off due to a power outage, the reel motor continues to rotate due to the inertia of the reel that was rotating just before the power outage, and a back electromotive force is generated in the reel motor. If the coil terminals of the reel motor are short-circuited at this time, the back electromotive force generates a braking force in the reel motor. The use of this braking force to stop the reel in a short time is called a "short brake."

[0013] If this short brake is applied only to the reel that is feeding out the magnetic tape during a power outage, the brake will only be applied to the reel that is feeding out, not the reel that is taking up the magnetic tape, so the reel that is taking up the magnetic tape will continue to rotate by inertia. As a result, the amount of magnetic tape that is fed out from the reel that is stopped by the short brake will be less than the amount of magnetic tape that is being taken up. In this case, tension will continue to be applied to the magnetic tape, and the magnetic tape will stop while being kept on its specified path.

[0014] Furthermore, Patent Document 1 discloses a brake mechanism for mechanically braking reels in a magnetic tape device. The brake mechanism disclosed in Patent Document 1 applies brakes to both reels simultaneously in the event of a power outage, preventing the magnetic tape from falling off the path. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] Japanese Patent Application Publication No. 05-266541 Summary of the Invention [Problem to be solved by the invention]

[0016] However, with the short brake and the brake mechanism disclosed in Patent Document 1, it is difficult to reliably prevent the magnetic tape from falling off the path in the event of a power outage. This will be explained below.

[0017] First, let's say a power outage occurs when most of the magnetic tape is on the feeding reel. In this case, the reel's rotation speed is slow, so the back electromotive force is small and the braking force of the short brake is small. In contrast, most of the magnetic tape remains on the feeding reel, so its own weight is heavy and it is difficult to stop. Therefore, it takes a long time for the feeding reel to stop, and the take-up reel, which has been rotating by inertia, stops first, making it unable to take up the magnetic tape. As a result, when the short brake is applied, the magnetic tape is fed out more than necessary, causing it to sag and fall off the path.

[0018] Furthermore, the brake mechanism disclosed in Patent Document 1 is designed to apply the brake simultaneously with the same force to both reels. Therefore, if a power outage occurs when most of the magnetic tape is on the reel that is being fed out, the brake mechanism disclosed in Patent Document 1 will also cause the reel that is being taken up to stop before the reel that is being fed out. As a result, just like in the case of a short brake, the magnetic tape will be fed out in excess and will sag, eventually falling off the path.

[0019] An example of an object of the present disclosure is to prevent a magnetic tape from falling off its path in the event of a power outage. [Means for solving the problem]

[0020] In order to achieve the above object, a magnetic tape device according to one aspect of the present disclosure comprises: a set of reel mechanisms for feeding and winding the magnetic tape by an electric motor; a brake mechanism configured to be able to apply a brake to the reel mechanism that is feeding out the magnetic tape; a control device that, when power supply to the electric motor is stopped, activates the brake mechanism for one of the reel mechanisms that is feeding out the magnetic tape; and The present invention is characterized in that it is provided with: [Effects of the Invention]

[0021] As described above, according to the present disclosure, it is possible to prevent the magnetic tape from falling off its path in the event of a power outage. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an example of a magnetic tape device. [Figure 2] FIG. 2 is a diagram specifically showing the brake mechanism for the magnetic tape shown in FIG. [Figure 3] FIG. 3 is a side view of the magnetic tape device shown in FIG. [Figure 4] FIG. 4 is a diagram showing the brake mechanism shown in FIG. 2 in an activated state. [Figure 5] FIG. 5 is a diagram showing an example of a timing chart in a magnetic tape device equipped with a brake mechanism. [Figure 6] FIG. 6 is a diagram showing an example of a timing chart for a conventional magnetic tape device that does not include a brake mechanism. [Figure 7] FIG. 7 is a diagram showing an example of the operation of each part in each situation of the magnetic tape device. [Figure 8] FIG. 8 is a top view showing the configuration of a conventional magnetic tape device. [Figure 9] FIG. 9 is a side view showing the configuration of a conventional magnetic tape device. [Figure 10] FIG. 10 is a diagram illustrating the forward operation in the magnetic tape device. [Figure 11] FIG. 11 is a diagram showing the change in the amount of tape taken up during forward movement. DETAILED DESCRIPTION OF THE INVENTION

[0023] (Embodiment) In the following, an example of a magnetic tape device will be described with reference to FIGS. 1 to 7 in the embodiment.

[0024] First, the schematic configuration of an example of a magnetic tape device will be described with reference to Fig. 1. Fig. 1 is a diagram showing the schematic configuration of an example of a magnetic tape device.

[0025] 1, a magnetic tape device 10 uses a magnetic head 16 to record and reproduce data on a magnetic tape 13 housed in a tape cartridge 11. As shown in FIG. 1, the magnetic tape 10 includes a pair of reel mechanisms 20 and 21, brake mechanisms 30 and 31, and a control device 40.

[0026] The reel mechanisms 20 and 21 each use an electric motor to feed and rewind the magnetic tape 13. The brake mechanisms 30 and 31 are provided for each reel mechanism and are configured to be able to apply a brake to the reel mechanism that is feeding out the magnetic tape 13.

[0027] When the power supply to the electric motors provided in the reel mechanisms 20 and 21 is stopped, the control device 40 activates the corresponding brake mechanism for one of the reel mechanisms that is currently feeding out the magnetic tape 13.

[0028] Also in Figure 1, reference numeral 12 denotes a cartridge reel driven by a reel mechanism 20. The cartridge reel 12 is provided in a tape cartridge 11. Furthermore, reference numeral 14 denotes a device reel driven by a reel mechanism 21. Reference numeral 19 denotes a housing, and only the outer edge is shown in Figure 1. Reference numeral 15 denotes a guide roller for guiding the magnetic tape 13 along a path.

[0029] In this way, in the event of a power outage, the magnetic tape device 10 is designed to brake only the reel mechanism that is unwinding the magnetic tape. Therefore, unlike when only a short brake is provided or when the brake mechanism disclosed in Patent Document 1 is provided, the magnetic tape is prevented from falling off the path without being wound up.

[0030] Next, the configuration of the magnetic tape device 10 will be specifically described with reference to Figures 2 to 4. Figure 2 is a configuration diagram specifically showing the brake mechanism of the magnetic tape shown in Figure 1. Figure 3 is a configuration diagram showing the configuration of the magnetic tape device shown in Figure 1 from the side. Figure 4 is a configuration diagram showing the state in which the brake mechanism shown in Figure 2 is activated. In Figures 2 to 4, the housing 19 is shown only by its outer edge.

[0031] 2 and 3, the brake mechanism 30 is provided in the reel mechanism 20, and the brake mechanism 31 is provided in the reel mechanism 21. The reel mechanism 20 also includes an electric motor 17 that rotates the cartridge reel 12. The cartridge reel 12 is connected to a shaft 17a of the electric motor 17 via a clutch 17b. The reel mechanism 21 also includes an electric motor 18 that rotates the device reel 14. The device reel 14 is connected to a shaft 18a of the electric motor 18.

[0032] The brake mechanism 30 is made up of a brake member 30a, a solenoid 30b, a coil spring 30c, a lever shaft 30d, and a fastener 30e. Similarly, the brake mechanism 31 is made up of a brake member 31a, a solenoid 31b, a coil spring 31c, a lever shaft 31d, and a fastener 31e.

[0033] The brake member 30a is arranged so as to be switchable between contact and non-contact with the cartridge reel 12 that constitutes the reel mechanism 20. Specifically, the brake member 30a has a shape that is long in one direction, and one end of the brake member 30a is rotatably held by a lever shaft 30d. The lever shaft 30d is arranged parallel to the shaft 17a and so that the brake member 30a can rotate about the lever shaft 30d to come into contact with the shaft 17a. The lever shaft 30d is fixed to the casing 19.

[0034] The solenoid 31b is disposed at the other end of the brake member 30a so as to be able to switch between contact and non-contact between the brake member 30a and the shaft 17a. Specifically, as shown in Fig. 2, the solenoid 31b is disposed so that operating the plunger causes the brake member 30a to rotate around the lever shaft 30d.

[0035] A coil spring 30c is disposed at one end of the brake member 30a to limit the rotation of the brake member 30a. Specifically, one end of the coil spring 30c is fixed to the brake member 30a, and the other end is fixed to a fastener 30e. The fastener 30e is fixed to the housing 19.

[0036] With this configuration, as shown in FIG. 2, in the brake mechanism 30, when power is supplied to the solenoid 31b, the plunger of the solenoid 31b protrudes, and the brake member 30a is out of contact with the electric motor 17 (shaft 17a).

[0037] On the other hand, as shown in FIG. 4, when the power supply to the solenoid 31b is stopped, the plunger of the solenoid 31b retracts, and the brake member 30a comes into contact with the electric motor 17 (shaft 17a) by the restoring force of the coil spring 30c and is further pressed against the electric motor 17, thereby braking the electric motor 17.

[0038] In the brake mechanism 31, the brake member 31a, the solenoid 31b, the coil spring 31c, the lever shaft 31d, and the fastener 31e are configured in the same manner as in the brake mechanism 30, and function in the same manner.

[0039] The control device 40 activates the brake mechanism 30 by controlling the solenoid 30b, and activates the brake mechanism 31 by controlling the solenoid 31b. Furthermore, the control device 40 activates a conventional short brake during a normal power outage, and can activate the brake mechanism 30 or the brake mechanism 31 in addition to the short brake during a specific power outage.

[0040] Here, the specific power outage is a power outage that occurs when the amount of magnetic tape wound up is small, the short brake is weak, and the magnetic tape 13 falls off the path. In other words, the specific power outage occurs when the amount of magnetic tape wound up in one of the reel mechanisms satisfies the set condition and the power supply to the motor is stopped. The set condition is determined in advance by experimentation by identifying the amount of wound magnetic tape 13 that would cause the magnetic tape 13 to fall off the path if only the short brake were applied.

[0041] Furthermore, the control device 40 determines whether the above-mentioned set conditions are met, for example, based on the time elapsed from the start of a forward or reverse operation in the magnetic tape device 10. Therefore, if the time from the start of a forward or reverse operation to the occurrence of a power outage is equal to or less than a threshold value corresponding to the above-mentioned set conditions, the control device 40 determines that the above-mentioned set conditions are met and activates the brake mechanism.

[0042] Next, the operation of the control device in the magnetic tape device 10 will be specifically described with reference to Figures 5 and 6. Figure 5 is a diagram showing an example of a timing chart in a magnetic tape device equipped with a brake mechanism. Figure 6 is a diagram showing an example of a timing chart in a conventional magnetic tape device not equipped with a brake mechanism.

[0043] 5 to 7 show the forward operation in which the magnetic tape moves from the cartridge reel 12 to the device reel 14. The power failure detection signal shown in FIGS. 5 to 7 is a signal input to the control device 40, and is activated by an electrical circuit built into the magnetic tape device 10 when the power supply voltage drops, and is in standby mode when the power supply voltage is normal. In other words, the power failure detection signal is automatically set to active or standby mode by the electrical circuit depending on the power supply voltage.

[0044] 5 and 7, the mechanical brake signal is a signal used by the control device 40 to control the brake mechanisms 30 and 31. Depending on the operating status (forward operation or reverse operation), the control device 40 sets the mechanical brake signal of the reel on the feeding side, either the cartridge reel 12 or the device reel 14, to active, and sets the mechanical brake signal of the reel on the winding side to standby.

[0045] As shown in Figures 5 and 7, during forward operation, the control device 40 sets the mechanical brake signal of the cartridge reel 12, which is the reel on the tape feed side, to active. Also, in the example of Figure 5, a power outage occurs when almost all of the magnetic tape 13 remains on the cartridge reel 12 on the feed side (a situation in which the above setting conditions are met). Therefore, the control device 40 immediately stops the supply of electricity to the solenoid 30b, activating the brake mechanism 30. Also, on the tape take-up side, the power supplied to the solenoid 31b gradually decreases due to the power outage and becomes zero when the power is lost.

[0046] On the other hand, during a reverse operation, the control device 40 sets the mechanical brake signal of the device reel 14 to active. If a power outage occurs when most of the magnetic tape 13 remains on the device reel on the delivery side, the control device 40, in contrast to the above, immediately stops the power supply to the solenoid 31b, thereby activating the brake mechanism 31.

[0047] 6, if the brake mechanisms 30 and 31 are not provided, only a short brake is used. In this case, a discrepancy occurs between the timing at which the take-up reel stops and the timing at which the feed reel stops. If such a discrepancy occurs, there is a possibility that the magnetic tape 13 may fall off the path.

[0048] Also, consider a situation where the tape cartridge 11 is not housed in the magnetic tape device 10, and a situation where the tape cartridge 11 is housed in the magnetic tape device 10 but the magnetic tape 13 is not moving. In such a situation, the control device 40 sets the mechanical brake signals of both reels to active.

[0049] In such a situation, if a power outage occurs and the power outage detection signal becomes active, each mechanical brake signal will be active, so the control device 40 will stop the power supply to each solenoid and activate each brake mechanism. As a result, even if the tape cartridge 11 is inside the magnetic tape device 10, each reel will be held in the stopped state it was in before the power outage by each brake mechanism, so the magnetic tape 13 will not slacken.

[0050] Also, in the above situation, when forward or reverse operation is initiated, the mechanical brake signal of the take-up reel is set to standby.

[0051] Here, the operation of each part in each situation of the magnetic tape device 10 will be described with reference to Fig. 7. Fig. 7 is a diagram showing an example of the operation of each part in each situation of the magnetic tape device.

[0052] As shown in FIG. 7, when the power failure detection signal is active and the mechanical brake signal is active, and the above set conditions are met, the control device 40 stops the power supply to the sending-side solenoid and activates the brake mechanism.

[0053] Furthermore, even if the power failure detection signal is active, if the mechanical brake signal is on standby, the control device 40 continues to energize the solenoid and keeps the brake mechanism released. In this case, if the power drops and the solenoid can no longer operate, the brake mechanism will be activated by the spring.

[0054] Furthermore, as shown in Figure 7, when power is normally supplied to the magnetic tape device 10, the power failure detection signal is in a standby state. In this case, regardless of the state of the mechanical brake signal, the control device 40 constantly energizes each solenoid and releases the brake mechanism. In this state, the operation of each electric motor is not impeded, and the forward and reverse operations that move the magnetic tape 13 are performed freely.

[0055] Next, a case where a power outage occurs during forward operation will be described with reference to Figure 7. First, when the tape cartridge 11 is housed in the magnetic tape device 10 and forward operation is being performed, the mechanical brake signal of the supply reel is active and the mechanical brake signal of the take-up reel is in a standby state. If a power outage occurs at this time, the power outage detection signal becomes active.

[0056] First, the control device 40 applies a short brake to the cartridge reel 12, which is the feeding reel, in the same manner as in the conventional system. Then, because the power outage detection signal is active and the mechanical brake signal of the cartridge reel 12 is active, the control device 40 cuts off the power supply to the solenoid 30b and activates the brake mechanism 30. By simultaneously applying this short brake and the brake mechanism 30, the cartridge reel 12 stops in a shorter time than in the conventional system.

[0057] Furthermore, the device reel 14, which is the take-up reel, rotates by inertia in the same manner as in the conventional configuration. Therefore, although the power outage detection signal is active, the mechanical brake signal of the device reel 14 is on standby, so the solenoid 31b continues to be energized and the brake mechanism 31 remains in the released state. Therefore, the device reel 14 is not hindered from rotating by inertia and stops in the same time as in the conventional configuration.

[0058] Therefore, the magnetic tape 13 is stopped by the supply reel, which has a shorter stopping time, and the take-up reel is stopped by being pulled by the magnetic tape 13, so that both reels stop with the magnetic tape maintaining tension. As a result, the magnetic tape 13 does not slacken and is maintained in its path. When the power is finally lost, the solenoid on the device reel 14 side is de-energized, and a mechanical brake is applied by the spring.

[0059] If a power outage occurs during reverse operation, the operation is reversed. In this case, both reels stop with the magnetic tape still in tension, and it remains in its path.

[0060] [Effects of the embodiment] As described above, the magnetic tape device 10 can apply a mechanical brake in addition to a short brake only to the reel mechanism that is feeding out the magnetic tape. Therefore, even if a power outage occurs when most of the magnetic tape remains on the cartridge reel 12 during forward operation, the magnetic tape can be prevented from falling off the path. [Industrial Applicability]

[0061] As described above, according to the present disclosure, it is possible to prevent the magnetic tape from falling off its path in the event of a power outage. [Explanation of symbols]

[0062] 10 Magnetic tape device 11 Tape cartridge 12 Cartridge Reel 13 Magnetic Tape 14 Device reel 15 Guide roller 16 Magnetic head 17 Electric motor 17a shaft 17b Clutch 18 Electric motor 18a shaft 19. Cabinet 20 Reel mechanism 21 Reel mechanism 30 Brake mechanism 30a Brake member 30b solenoid 30c coil spring 30d lever shaft 30e fastener 31 Brake mechanism 40 Control device

Claims

1. a set of reel mechanisms for feeding and winding the magnetic tape by an electric motor; a brake mechanism configured to be able to apply a brake to the reel mechanism that is feeding out the magnetic tape; a control device that, when power supply to the electric motor is stopped, activates the brake mechanism for one of the reel mechanisms that is feeding out the magnetic tape; and Equipped with When the amount of the magnetic tape wound by one of the reel mechanisms satisfies a set condition and the power supply to the electric motor is stopped, the control device generating a brake by short-circuiting the motor of the other reel mechanism that is feeding out the magnetic tape; and a brake mechanism for operating the other of the reel mechanisms that is feeding out the magnetic tape;

2. the brake mechanism is provided for each of the reel mechanisms in a set, a brake member arranged so as to be switchable between contact and non-contact with the reel constituting the reel mechanism; a solenoid that keeps the brake member out of contact with the electric motor when power is being supplied to the electric motor; Equipped with 2. The magnetic tape device according to claim 1.

3. The control device activates the brake mechanism by controlling the solenoid.

3. The magnetic tape device according to claim 2.

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