JPH04195754A - Tension controller - Google Patents

Abstract

PURPOSE:To obtain an always stable tape tension by generating two or more pulses at an arbitrary interval between an initial latch pulse and a second latch pulse, and adding it to a latch pulse. CONSTITUTION:The output of a latch pulse generator 11 is input to a latch pulse additional circuit 16, two or more pulses at an arbitrary interval between an initial latch pulse generated from the generator and a second latch pulse are generated, and a pulse is further added to the latch pulse generated from the the generator 11. Thus, the circuit 16 is provided, the output of the generator is connected to the input, and the output of the additional circuit is supplied to a first latch circuit 9, a second latch circuit 7 and a winding diameter detector 12. Thus, a tape tension responsive to the diameter can be set in a short time, and a suitable torque responsive to the winding diameter of the tape can be generated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tension control device used in a magnetic recording/reproducing device to keep the tension of a tape constant.

BACKGROUND OF THE INVENTION FIG. 3 is a block diagram showing an example of a tension control device used in a conventional magnetic recording/reproducing device, and FIG. 4 is a timing chart thereof.

In FIG. 3, 4 is a capstan motor for transporting the magnetic tape, and 14 is provided on the capstan motor, and generates a frequency signal (hereinafter referred to as CAPFG signal) having a frequency proportional to the rotational speed of the capstan motor 4. A first frequency generator (hereinafter referred to as CAPFG) 5 is pressed to a capstan motor 4 and is a pinch roller for transporting the tape, 3 is a tape, 2 is a take-up reel for winding the transported tape, 1 is a reel motor 15 that drives a take-up reel, and a second frequency generator (hereinafter referred to as a reel FG signal) that is installed in the reel motor and generates a frequency signal (hereinafter referred to as a reel FG signal) having a frequency proportional to the rotational speed of the reel motor 1. (hereinafter referred to as reel FG) 10 is a cent pulse generation circuit that generates a reset pulse every cycle T1, and 6 is a second counter that counts the reel FG signal and is reset by a pulse from the reset pulse generation circuit. , 8 is a first counter that counts the CAPFG signal and is reset by a pulse from the reset pulse generation circuit, 11 is a latch pulse generation circuit that generates a latch pulse at a period T1, and 7 is the second counter. a second latch circuit that latches the count value using a latch pulse generated by the latch pulse generation circuit; 9 a first latch that latches the count value of the first counter using a latch pulse generated from the latch pulse generation circuit; 12 is a winding diameter detection circuit for determining the winding diameter for each latch pulse from the output of the first latch circuit and the output of the second launch circuit; 13 is a drive circuit for rotating the reel motor 1; be.

The operation of the tension control device configured as described above will be explained below.

First, in FIG. 3, the tape 3 is transported by a capstan motor 4 and a pinch roller 5 pressed against the capstan motor 4. This transferred tape 3 is wound onto a take-up reel 2 by a reel motor 1. The CAPFG signal (b) with a frequency proportional to the rotational speed of the capstan motor 4 is the first
It is counted by a counter 8 and is reset by a pulse from a reset pulse generation circuit 10 which generates a reset pulse every cycle T1. On the other hand, the FG signal (a+), which is proportional to the rotational speed of the reel motor 1, is counted by a second counter and reset by a pulse from the reset pulse generation circuit 10.The count value of the tenth counter is The latch pulse generated by the latch pulse generation circuit 11 is latched by the first latch circuit.Similarly, the count value of the second counter is latched by the latch pulse generated by the latch pulse generation circuit 11.
It is latched by the latch circuit. Next, from the output of the first launch circuit and the output of the second latch circuit, a detection signal proportional to the tape winding diameter is obtained by the winding diameter detection circuit 12 every period T1 of the latch pulse, and the drive circuit 13 and the reel motor 1, the tension of the tape 3 is kept constant regardless of the winding diameter. The reset pulse from the reset pulse generation circuit 10 is generated immediately after the latch pulse from the latch pulse generation circuit 11 is generated, as shown in the timing chart of FIG.

Problems to be Solved by the Invention However, in the tension control device with the conventional configuration described above, the detection period T1 is lengthened to reduce the winding diameter detection error. Since unrelated signals are output, the tape tension is not determined, which causes the tape to run unstable.

The present invention has been made in view of such conventional tension control devices, and its technical problem is to ensure that stable tape tension is always obtained.

Means for Solving the Problems In order to solve the above problems, the tension control device of the present invention includes:
a take-up reel; a first frequency power generating means that detects the amount of tape travel and generates a frequency proportional to the tape speed;
a first counter connected to the output of the first frequency power generation means; a first latch means connected to the output of the first counter; a second frequency power generation means for generating a frequency proportional to the second frequency power generation means; a second counter connected to the output of the second frequency power generation means; a second latch means connected to the output of the second counter; and a winding diameter detecting means connected to each output of the second latch means, a reset pulse generation circuit connected to the first counter and the second counter, and the first and second latch means and the winding diameter detecting means. a latch pulse applying means connected to each of the latch pulse applying means, a latch pulse generating means connected to the input of the latch pulse applying means, a driving means connected to the output of the winding diameter detecting means, and a driving means connected to the output of the driving means. It has a structure consisting of a take-up reel.

According to the present invention, when the winding diameter mode signal level changes due to the above-described configuration, the latch pulse adding means operates to increase the interval between the first latch pulse and the second latch pulse generated by the launch pulse generation circuit by two or more. Pulses divided into arbitrary intervals are generated and added to the latch pulses generated by the latch circuit.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a tension control device according to an embodiment of the present invention, and FIG. 2 is a timing chart thereof.

In FIG. 1, 4 is a capstan motor for transporting the magnetic tape, and 14 is provided on the capstan motor, and generates a frequency signal (hereinafter referred to as CAPFG signal) with a frequency proportional to the rotational speed of the capstan motor 4. A first frequency generator (hereinafter referred to as CAPFG) 5 is pressed to a capstan motor 4 and is a pinch roller for transporting the tape, 3 is a tape, 2 is a take-up reel for winding the transported tape, 1 is a reel motor 15 that drives a take-up reel, and a second frequency generator (hereinafter referred to as a reel FG signal) that is installed in the reel motor and generates a frequency signal (hereinafter referred to as a reel FG signal) having a frequency proportional to the rotational speed of the reel motor 1. (hereinafter referred to as reel FC) 10 is a reset pulse generation circuit that generates a reset pulse every cycle T, 6 is a second counter that counts the reel FG signal and is reset by the reset pulse, 8 is the CAPFG signal 11 is a latch pulse generation circuit that generates a latch pulse at a period TI, and 16 is a latch pulse generation circuit that generates a latch pulse in accordance with the winding diameter mode command e. The latch pulse generation circuit 11 generates pulses in which the interval between the first launch pulse and the second launch pulse is divided into two or more arbitrary intervals.
Lunch pulse addition circuit that adds pulses to Sochi pulse,
7 is a second latch circuit that latches the count value of the second counter with a pulse output from the latch pulse addition circuit; 9 is a second latch circuit that latches the count value of the first counter with the pulse output from the latch pulse addition circuit; a first launch circuit that launches based on a pulse; 12 is a detection circuit that determines the winding diameter for each pulse output from the latch pulse addition circuit 16 from the output of the first launch circuit and the output of the second latch circuit; 13 is a drive circuit for rotating the reel motor 1. - The operation of the tension control device of this embodiment configured as described above will be explained below.

First, in FIG. 1, the tape 3 is transported by a capstan motor 4 and a pinch roller 5 pressed against the capstan motor 4. This transferred tape 3 is wound onto a take-up reel 2 by a reel motor 1. Reset pulse generation circuit 10
The latch pulse generating circuit 11 starts operating in response to a mode for controlling the torque of the motor according to the winding diameter, that is, a winding diameter mode indicator g. The reset pulse C generated by the reset pulse generation circuit and the launch pulse generated by the latch pulse generation circuit are signals as shown in FIG. 2, and the latch pulse generation circuit operates at the same time as the winding diameter mode signal becomes H level. A latch pulse f is generated every cycle T1, and immediately thereafter a reset pulse, which is the output of the reset pulse circuit, is generated every cycle T+.

The output of the latch pulse generation circuit 11 is input to the latch pulse addition circuit 16, and the interval between the first latch pulse and the second latch pulse generated by the latch pulse generation circuit is set to an arbitrary number of two or more, for example, in this embodiment. In this case, pulses divided into six are generated, and a further pulse is added to the latch pulse generated by the latch pulse generation circuit 11. On the other hand, CAPF with a frequency proportional to the rotational speed of the capstan motor 4
The G signal (bl is counted by the first counter 8 and reset by a pulse from the reset pulse generating circuit. On the other hand, the reel FG signal (a+ is counted by the second counter 8) which is proportional to the rotational speed of the reel motor 1. The count value of the first counter is counted by the pulse generated by the latch pulse addition circuit 16 and reset by the pulse from the reset pulse generation circuit 10.
It is latched by the latch circuit. Similarly, the count value of the second counter is latched by the second latch circuit using a pulse generated by the latch pulse addition circuit 16. Next, each time a pulse generated from the latch pulse addition circuit 16 arrives, a detection signal proportional to the tape winding diameter is obtained by the winding diameter detection circuit 12 from the output of the first latch circuit and the output of the second latch circuit. , the drive circuit 13, and the reel motor 1 to keep the tension of the tape 3 constant regardless of the winding diameter.

As described above, according to this embodiment, the latch pulse addition circuit 16 is provided, and the output of the latch pulse generation circuit is connected to its input, and the output of the latch pulse addition circuit is sent to the first latch circuit 9 and the second latch circuit, respectively. 7 and the winding diameter detection circuit 12.

As described in detail, according to the present invention, it is possible to set the tape tension according to the tape winding diameter in a short time, and to generate an appropriate torque according to the tape winding diameter, thereby realizing stable tape running. can be done, and its practical effects are great.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a tension control device in one embodiment of the present invention, FIG. 2 is a timing chart of this embodiment, and FIG.
The figure is a block diagram showing the configuration of a conventional tension control device.
The figure is a timing chart of a conventional tension control device. 1...Reel motor, 2...Take-up reel, 3...Tape, 4...Capstan motor, 5...Pinch roller , 6...
・Second counter, 7...Second latch circuit,
8...First counter, 9...First latch circuit, 10...Reset pulse generation circuit, 11...Latch pulse generation circuit, 12 ...
... Winding diameter detection circuit, 13 ... Drive circuit, 14
...First frequency generator (CAPFG), 1
5...Second frequency generator (reel FG), 1
6...Latch pulse addition circuit. Name of agent Patent attorney Haruaki Ogata et al. 22 No. 1 Figure 3 Figure 4 ' Ra V + No Lus f

Claims (1)

[Claims] a take-up reel; a first frequency power generating means that detects the amount of tape travel and generates a frequency proportional to the tape speed;
a first counter connected to the output of the first frequency power generation means; a first latch means connected to the output of the first counter; a second frequency power generation means for generating a frequency proportional to the second frequency power generation means; a second counter connected to the output of the second frequency power generation means; a second latch means connected to the output of the second counter; and a winding diameter detecting means connected to each output of the second latch means, a reset pulse generation circuit connected to the first counter and the second counter, and the first and second latch means and the winding diameter detecting means. a latch pulse applying means connected to each of the latch pulse applying means, a latch pulse generating means connected to the input of the latch pulse applying means, a driving means connected to the output of the winding diameter detecting means, and a driving means connected to the output of the driving means. A tension control device consisting of a take-up reel.