JPS6329353A - Tape traveling controller - Google Patents

Abstract

PURPOSE:To attain the searching of the position of a magnetic tape by providing a signal processing circuit to remove a signal from the output of a head, quickening and delaying successively tape traveling speed with a tape speed setting means, reading position information on the magnetic tape and controlling the traveling of a tape. CONSTITUTION:A command is issued even to a cylinder speed setting means 9 so that a tape traveling speed is changed by a tape speed setting means 8 and simultaneously, a track direction speed on a tape 2 of heads 13a and 13b comes to be constant, and the rotation speed of a cylinder 1 is changed. In such case, when the changing quantity of a tape travelling speed is larger, the track direction speed component of the heads 13a and 13b is not constant at a transition period, a data rate is changed and the position information on the track cannot be read. Then, the changing quantity of the traveling speed the tape 2 is set to a small quantity each time, instead of it, the number of the setting of the tape traveling speed set by the tape speed setting means 8 is made plural, the speed is changed finely and the data are not overlooked in reading even at the time of the transition period.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tape running control device capable of reading tape position information of a rotary head type digital audio tape recorder or the like even when a magnetic tape is being fed at high speed.

Conventional technology Conventional tape recorders and video tape recorders (hereinafter referred to as V
When searching for the tape position of a magnetic tape on which desired music or video is recorded, calculations based on counting the CTL signals recorded by a fixed head or the same method (written as TR) can be used.
This has been done by reading address signals recorded on cueing tracks by fixed heads. (For example, "Video Editing Technology," written by Yo Ogawa, published by Kenrokukan Publishing, pp. 43-45) Problems to be Solved by the Invention In such conventional technologies, fixed heads dedicated to CTL signals and queuing tracks are not used. had to be established.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a tape running control device that can search for a desired magnetic tape position without a fixed head.

Means for Solving the Problems In order to solve the above problems, the present invention records information by forming diagonal tracks on a magnetic tape, and records position information on the magnetic tape at a predetermined position on each track. tape running control means for running the magnetic tape at a higher speed than when normally reproducing signals recorded on the magnetic tape; tape speed setting means for setting a plurality of tape speeds to the tape running control means; A cylinder to which a magnetic head is attached and whose rotation is controlled and its control circuit, and a tape speed setting means to set the speed to a tape travel control means, the cylinder rotation speed is synchronously changed to the track direction velocity component of the head attached to the cylinder. The configuration includes a cylinder speed setting means that sets the rotation speed to be the same as that during normal playback, and a signal processing circuit that processes the output of the head attached to the cylinder and extracts a signal. It is constructed so that positional information on the tape can always be read even when the running speed is gradually increased or decreased.

Effect of the Invention With the above-described structure, the cylinder speed setting means makes it possible for the relative speed of the head in the track direction to be the same whether the magnetic tape is played back at a normal speed or when it is run at high speed. Therefore, it becomes possible to read the position information of the magnetic tape recorded on the track.

In addition, during the transition period when changing the tape speed, by selecting the tape speed set by the tape speed setting means in appropriate steps, it is possible to eliminate the possibility of missing position information, and it is possible to avoid missing position information, such as when searching for the position of the magnetic tape. We will work to make this possible.

Embodiment FIG. 1 is a block diagram showing an embodiment of the tape running control device of the present invention.

In FIG. 1, 1 is a cylinder to which hefts 13a and 13b are attached, 2 is a magnetic tape, and 5 is a reel 1.
The cylinder 1 is stretched by the glue 2 and the post 3.4 so as to be in skin contact with the cylinder 1 at a predetermined angle.

The outputs of the heads 13a and 13b are applied to the signal processing circuit 11 via a rotary transformer or a slip ring (both not shown) and processed. A cylinder FG12 is provided in the cylinder 1 so as to share a rotating shaft, and operates to generate a pulse signal proportional to the number of rotations of the cylinder 1. IO is a cylinder control circuit, and cylinder F
Cylinder 1 is rotated at a constant speed based on the output of G12. 7
is a tape running control means, and reel FG1 of 701 is provided on reel 1 and reel 2, respectively, sharing a shaft.
702 reel FG2 and 703 FV converter 1 and 7
04 FV converter 2, drive circuit 706 and adder 70
It consists of 5. Further, 8 is a tape speed setting means, which is connected to the cylinder control circuit 1 via cylinder speed setting means 9.
0 to change the number of rotations of the cylinder 1, and also issues a command to the tape running control means 7 to change the tape running speed.

One embodiment of FIG. 1 has the above configuration, and the tape running speed is changed by the tape speed setting means 8, and at the same time, the head 13a
, 13b on the tape 2 in the track direction becomes constant by issuing a command to the cylinder speed setting means 9 so as to change the rotational speed of the cylinder 1. At this time, if the amount of change in the tape running speed is large, the change in the rotational speed of cylinder 1 and the change in the running speed of tape 2 are generally not the same (since either one is faster, heads 13a, 1
The track direction velocity component of 3b is not constant, the data rate changes, and position information on the track cannot be read. In the present invention, the amount of change in the running speed of the tape 2 is set small each time, and instead, a plurality of tape running speeds can be set by the tape speed setting means 8, and the speed is finely changed to allow transient We ensure that no data is overlooked even during periods.

FIG. 2 shows an example of the configuration of FV converter 1 (703) in tape running control means 7 according to the present invention, and FV converter 2 (704) is similarly configured. Further, FIG. 3 shows the cylinder speed setting means 9 and the cylinder control circuit 10.
This is a configuration example. A more detailed explanation will be given based on these drawings.

In FIG. 2, 721 is a clock oscillator, 722 to 7
25 are each 1/12. 1/6. 1/4. 1/3
A frequency divider 726 is a selector for each of the frequency dividers 722 to 7.
25 is selected by a command from the tape speed setting means 8.

A counter 727 counts the clock selected by the selector 726. 728 is a launch pulse generator that outputs a latch pulse that latches the output value of the counter 727 with the latch 729 when the reel FG 1 (701) outputs a pulse, and a reset pulse that resets the counter 727 after latching with the latch 729. . 730 is D/A
Output cuff 3 of FV converter 1 (703) with converter
1 is the output of the D/A converter 730.

Figure 2 shows the above configuration, and the reel FG 1 (70
The analog output cuff 31 corresponding to the output pulse period of 1) is output. At this time, the signal selected by selector 726 is 171
2, 1/6. 1/4. There are four types of 1/3, with a relative ratio of l:2:3:4, and the rotational speed of the reel is xl, x2. x3. It is set so that the same analog output cuff 31 can be obtained when x4. The tape running control means 7 in FIG. 1 controls tape running by the sum of the outputs of FV converter 1 (703) and FV converter 2 (704), and the tape winding diameter of reel 1 (5) and reel 2 (6) is However, depending on the clock selected by the selector 726, a tape speed of x1 to x4 can be obtained. For example, 173 minute period 7
If the tape speed when output number 25 is selected is set to 100 times the normal playback speed, then the tape speed will be 1/12. 1/6.
1/4. By selecting the output of each frequency divider 722 to 725 of 1/3×25°×50. x75. X100
It is possible to set four types of tape speeds.

Although the above explanation has shown examples of four types of frequency dividers, it is not necessary to limit the number to four (and it is clear that the frequency division ratio can also be selected outside the side base of FIG. 2).

Next, the speed setting of cylinder l will be explained.

In FIG. 3, the cylinder speed setting means 9 consists of a continuous read only memory (hereinafter abbreviated as ROM) 902 and an address setting circuit that generates an address for the ROM 902 in response to a command from the tape speed setting means 8. The address setting circuit 901 is composed of four addresses and selectors corresponding to the tape running speed. Cylinder control circuit 10
is the latch pulse generator 101. Counter 102. Latch 103. D/A converter 104. It consists of a drive circuit 105, and when the cylinder FG12 generates a pulse, the launch pulse generator 101 generates a latch pulse in response to the pulse, latches the output value of the counter 102 with the latch 103, and immediately thereafter generates a preset pulse. The counter 102 is reset to the value output by the ROM 902. The output of the launch 103 is converted into an analog value by the D/A converter 104 and is given to the drive circuit 105, and its output 10
At 6, the cylinder 1 is driven by a cylinder drive motor (not shown) sharing a shaft. Since the cylinder rotational speed and D/A output change depending on the value presented to the counter 102, the cylinder 1 can be set at four different rotational speeds by the tape speed setting means 8 in the same manner as the tape running speed.

Of course, as already mentioned, the relationship between the tape running speed and the rotational speed of the cylinder 1 is subject to the condition that the track direction component of the head is constant.

Next, a description will be given of how the tape running control device configured as described above behaves in a transient state where the tape speed changes.

FIG. 4 shows a diagram showing a transient state. In FIG. 4, horizontal axes 42.46 both indicate time, and 42.46 are on the same time scale. The vertical axis 41 represents the tape running speed.

This is the cylinder rotation speed, and the actual tape running speed is indicated by the dotted line 44. The cylinder rotation speed is indicated by a solid line 43.

Further, the vertical axis 45 represents the relative speed error of the hefts 13a and 13b in the track direction, and 47 represents the relative speed error in a transient state. Reference numeral 48 indicates the permissible variation rate of the data signal of the signal processing circuit 11 in FIG.

As shown in FIG. 4, the transient response 43 of cylinder 1
and the transient response 44 of the tape running speed. Therefore, the track direction velocity component of heads 13a and 13b is 47
As in, there will always be errors. However, the signal processing circuit 1
If 48 is within the allowable range of 1, the data can be read reliably, so as shown in FIG. and the amount of change in tape speed.

Effects of the Invention As described above, according to the present invention, if the tape is run at high speed in appropriate steps, the error in the velocity component of the head in the track direction can be kept small even in a transient state, and the tape position on the track can be adjusted. It is extremely effective in practical use, as information can be reliably read and tapes can be easily searched and edited at high speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIGS. 2 and 3 are FV converter 1 of the embodiment shown in FIG. 1.
FIG. 3 is a block diagram showing an example of the configuration of the cylinder speed setting means and cylinder control circuit of the embodiment shown in FIG. FIG. 4 is an explanatory diagram for explaining the transient state. 7... Tape running control means, 8... Tape speed setting means, 1... Cylinder, 10...
... Cylinder control circuit, 9 ... Cylinder speed setting means, 11 ... Signal processing circuit. Name of agent: Patent attorney Toshio Nakao Figure 1 - J 4
figure

Claims (2)

[Claims] (1) A device for playing back a magnetic tape in which information is recorded by forming diagonal tracks on the magnetic tape, and position information of the magnetic tape is recorded in a predetermined position on each track,
A tape running control means for running a signal recorded on a magnetic tape at a higher speed than when normally reproducing a signal, a tape speed setting means for setting a plurality of tape speeds to the tape running control means, and a magnetic head are attached. A cylinder whose rotation is controlled, a cylinder control circuit which controls the rotation of the cylinder, and a head attached to the cylinder which adjusts the cylinder rotational speed in synchronization when the tape speed setting means sets the speed to the tape running control means. and a signal processing circuit for processing the output of the head attached to the cylinder to extract a signal. 1. A tape running control device that controls tape running by reading positional information on a magnetic tape while sequentially speeding up or slowing down the tape running speed using a tape speed setting means. (2) The tape running control means may include a clock pulse generation circuit and a counter circuit for counting the clock pulses, and the tape speed setting means may set the clock frequency of the clock pulse generation circuit of the tape running control means. The tape running control device according to claim (1), characterized in that the tape running control device is configured so as to be able to perform the following operations.