JPS6242324B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tone arm driving device that is capable of accurately positioning a tone arm with respect to an introduction groove of a record based on a reference position provided within a movement range of the tone arm. .

In conventional auto players, a DC motor has been used as a drive source for horizontally moving the tone arm. Therefore, a brake device must be installed to accurately position the pick-up cartridge provided at the tip of the tone arm over the sound groove (hereinafter referred to as the introduction groove) provided on the outer periphery of the record for entering the performance. It was impossible. This is because the radial width of the introduction groove provided on the record is very narrow, and the length of the tone arm arm is generally about 200 mm.
This is because slight variations at the base of the tone arm become large variations at the tip.

Therefore, in the conventional autoplayer, it is necessary to provide a brake device in order to accurately position and stop the pick-up cartridge on the introduction groove, which causes the problem that the mechanism becomes complicated. Also, since it uses a DC motor,
In particular, controlling the moving speed and rotation direction of the tone arm using a digital circuit or microcomputer not only complicates the structure but also increases the number of parts, resulting in high costs.

The present invention solves the above problems, and the gist thereof is: a pulse motor driven by pulses from an oscillation circuit to horizontally move a tone arm from its armrest position to a playing start position of a record; and a record. size detecting means for detecting the size of the tone arm; a reference position detection means that is provided at one location within the movement range and detects that the tone arm has arrived at the reference position and outputs a detection signal; and upon receiving the detection signal from the reference position detection means, the oscillation circuit a counter circuit that starts counting pulses from the recorder and outputs a signal representing the count value; and a counter circuit that receives the output signal of the counter circuit and determines the amount of movement of the tone arm from the reference position to the playing start position of the record. The tone arm drive device comprises: motor stop control means for stopping the pulse motor when a count value of the counter circuit is preset with a pulse value corresponding to the pulse value and the count value of the counter circuit matches the pulse value.

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

In FIG. 1, reference numeral 1 denotes a motor stop position detection circuit means, and the motor stop position detection circuit means 1 is constructed as shown in FIG. 2 is a start switch, and the start switch 2 is connected to the input terminal 4a of the OR gate 4 via the flip-flop 3.
The other input terminal 4b of the OR gate 4 is connected to the output terminal of a motor signal circuit 25, which will be described later. A control drive circuit 5 is connected to the output end of the OR gate 4, and a pulse motor M is connected to the output end of the control drive circuit 5. Note that the pulse motor M is driven by pulses.

7 is the size of the record (e.g. 17cm, 30cm
etc.), and in the embodiment, it is manually operated.
When the contact is open, the size of the record is 17 cm, and when it is closed, the size is 30 cm. Note that there are other sizes of record discs, so it may be possible to detect all of these sizes.Also, although the size of the record disc was detected manually, it is not possible to detect it automatically. You can do it like this.

The size detection switch 7 is connected to an input end of a NAND gate 8 and also connected to an input end of a NAND gate 10 via an inverter 9.

11 is a reference position detection sensor;
Pickup Cart Tsuji is a vinyl record (30
It is designed to operate when it reaches a preset reference position outside of cm), and a phototransistor is used in the embodiment.

The collector of the phototransistor 11 is connected via an inverter 12 to the input terminals of a flip-flop 13 and a Nant gate 10, and the output terminals of the Nant gates 8 and 10 are connected to inverters 14 and 1, respectively.
5 to the input end of the NOR gate 16,
An output terminal 16a of the NOR gate 16 is connected to a reset terminal of the flip-flop 3 and also to a plunger circuit to be described later.

The output terminal of the flip-flop 13 and the output terminal of the oscillator 17 are connected to the input terminal of an AND gate 18, and the output terminal of the AND gate 18 is connected to the counter 19.
The output terminal of the oscillator 17 is connected to the input terminal of the control drive circuit 5. counter 19
Decoders 20 and 21 that count a preset number of pulses in order to move the tone arm to the lead-in groove of the record are connected to the output end of the record, and the start switch 2 is connected to the reset terminal of the counter 19, and the decoder The output terminal of decoder 20 is connected to the input terminal of NAND gate 8 and the reset terminal of flip-flop 3, and the output terminal of decoder 21 is connected to the input terminal of NAND gate 10. here,
The decoder 20 counted the number of pulses set to move the tone arm to the lead-in groove of a 17 cm record, and the decoder 21 was set to move the tone arm to the lead-in groove of a 30 cm record. Count the number of pulses. Here, NAND gates 8 and 10, flip-flop 13, Noah gate 16, and gate 1
8, a counter 19, decoders 20, 21, etc. constitute a motor stop position detection circuit 22.

23 is a motor signal circuit means, and 24 is a rotation direction switching circuit means, an embodiment of which will be explained in detail with reference to FIG. A flip-flop is used as the motor signal circuit 25.
The OR gate 26 is connected to the input terminal of the OR gate 26, and the output terminal 1 of the OR gate 16 is connected to the input terminal of the OR gate 26.
6a and tone arm end position detection sensor 27
The output terminal of the flip-flop 25 is connected to the reset terminal of the tone arm 28, and the output terminal of the flip-flop 25 is connected to the input terminal 4b of the OR gate 4.

The input end of the AND gate 29 is connected to an output end 44a of a latch circuit, which will be described later, and a tone arm rise detection switch 30, and the output end of the AND gate 29 and the output end 16a of the OR gate 16 are connected to the input end of the OR gate 31. Connected, or gate 3
1 is connected to a reset terminal of a flip-flop 32 as a rotation direction switching circuit.
A rest detection switch 33 that detects whether the tone arm is on the armrest and a start switch 2 are connected to the input end of an AND gate 34.
The lowering detection switch 28 and the sensor 27 are connected to the input terminal of the AND gate 35, and the AND gate 3
The output terminals of the flip-flops 4 and 35 are connected to the input terminal of the NOR gate 36, the output terminal of the NOR gate 36 is connected to the set terminal of the flip-flop 32, and the output terminal of the flip-flop 32 is connected to the input terminal of the control drive circuit 5.

FIG. 4 shows plunger control circuit means 42 for controlling plunger 38 which switches clutch 41 to raise and lower the tone arm by means of a tone lifter. A rise detection switch 30 is connected to the input end of a flip-flop 37 serving as a plunger control circuit, and the output end thereof is connected to a plunger 38. The rest detection switch 33 and the output terminal 44a of the latch circuit are connected to the input terminal of the AND gate 39, and the output terminal of the AND gate 39 and the output terminal 16a of the NOR gate 16 are connected to the input terminal of the OR gate 40. The output terminal is connected to the reset terminal of flip-flop 37.

Here, the clutch 41 causes the tone arm to be horizontally moved by the motor M when the plunger 38 is in an operating state, and by the motor M when the plunger 38 is in an inactive state.
The tone arm is switched to operate the arm lifter to raise and lower the tone arm.

FIG. 5 shows the latch circuit means 43 for holding the signal of the end position detection sensor 27. The sensor 27 is connected to the input end of the flip-flop 44 as a latch circuit, and the output end 44a of the flip-flop 44 is connected to the input end of the AND gate 39 and the AND gate 29. At the input terminal of the AND gate 45, there is a switch 3.
0 and 33 are connected, and the output terminal of the AND gate 45 is connected to the reset terminal of the flip-flop 44.

The operation of moving the tone arm using the apparatus of the present invention will be explained below with reference to FIGS. 2 to 6.

When the start switch 2 is turned on, a signal is sent to the control drive circuit 5 via the flip-flop 3. At the same time, a signal is sent to the AND gate 34. In this state, an output is generated at the OR gate 36, a normal rotation signal is input to the circuit 5, and the oscillator 1
The motor M rotates forward in response to the pulse signal from the tone arm 7, and since the plunger 38 is inactive in this state, the tone arm is raised by the arm lifter. In this state, the tone arm is on the armrest, so the rest detection switch 33 is turned on. Then, when the tone arm rises to the set height, the rise detection switch 30 is turned on.
Therefore, switches 30 and 33 are placed in AND gate 45.
Flip-flop 44 is cleared in order for the signal to be sent out.

The signal from switch 30 is sent to flip-flop 37.
A signal from the flip-flop 37 causes the plunger 38 to remain in operation. When the plunger 38 operates, the clutch 41 is switched and the pulse motor M causes the tone arm to move horizontally toward the record side.

When the tone arm reaches the reference position, the reference position detection sensor 11 is turned on. Note that x is the moving distance from the reference position when the record size is 30 cm until the tone arm starts to descend to match the record size.

Here, the record size is 17 cm, so the record size detection switch 7 is
It is OFF, and the signal of switch 7 is a high signal.

A high signal from switch 7 is input to NAND gate 8, and a low signal from sensor 11 is input to flip-flop 13 via inverter 12. and,
Flip-flop 13 operates and AND gate 1
Continue to send a high signal to 8. Then, the pulse sent from the oscillator 17 is input to the AND gate 18, and the counter 19 starts counting.
When the counter 19 counts the preset number of pulses to move the tone arm to the introduction groove of a 17 cm record, the decoder 20 outputs a high signal. Then, this high signal is input to the NAND gate 8, and the inverter 14,
A stop signal is sent to output terminal 1 via NOR gate 16.
6a, and flip-flop 3 is reset.

The stop signal from the NOR gate 16 is input to the reset terminal of the flip-flop 32 via the OR gate 31. The control drive circuit 5 sends a reverse rotation signal to the pulse motor M in response to a signal from the flip-flop 32. At the same time, a stop signal is input to the reset terminal of the flip-flop 3 and the OR gate 26. Therefore, the stop signal via the OR gate 26 is input to the flip-flop 25, this signal is instantaneously switched via the OR gate 4 and input to the control drive circuit 5, and the pulse motor M is reversed by the pulse signal from the oscillator 17. be rotated.
At this time, since the plunger 38 is OFF, the arm lifter is reversely rotated by the pulse motor M, and the tone arm is lowered. When the lowering detection switch 28 detects the lowering of the tone arm, the flip-flop 25 is reset and the output of the OR gate 4 disappears, so that the pulse motor M is stopped. In this state, the pickup cartridge of the tone arm traces the tone groove of the record, and the instrument is in a playing state.

When the performance ends, the inward speed of the tone arm becomes faster than during the performance due to the sound groove of the record, so the end position detection sensor 27 detects this and turns on. When the output of the sensor 27 enters the input terminal of the flip-flop 44, the flip-flop 44 is turned on.

As a result, an output is generated at the OR gate 31, and a normal rotation signal is output from the flip-flop 32 to the control drive circuit 5.
is input, and the pulse motor M rotates forward. At this time, since the plunger 38 is inactive, the tone arm is raised by the arm lifter.

When the rise detection switch 30 is turned on, the plunger 38 is operated and the clutch 41 is switched. On the other hand, since the lowering detection switch 28 is OFF, an output is generated at the OR gate 36, and a reverse rotation signal is input to the circuit 5, so that the pulse motor M is reversed. As a result, the tone arm is horizontally moved toward the armrest.

When the tone arm reaches the armrest position, the rest detection switch 33 is turned on, and the plunger 38 becomes inactive. Since the pulse motor M is rotating in reverse, the tone arm is lowered by the arm lifter and supported by the arm left. Then, the pulse motor M stops.

In the embodiment, the reference position of the tone arm is set outside the record, but if the reference position of the tone arm is matched to the lead-in position of a 30 cm record, for example, one decoder 21 can be omitted, simplifying the configuration. can be achieved.

Further, in the embodiment, the explanation of the initial (main switch) reset of the flip-flop is omitted.

As described above, since the present invention uses a pulse motor, the tone arm can be stopped at a predetermined position without providing a brake device, and the configuration can be simplified. Since the number of pulses is set and controlled, the tone arm can be easily stopped at multiple locations using one reference position detection sensor.
Furthermore, since the pulses from the oscillation circuit between the armrest position and the reference position when the tonearm is moving are not subject to stop control, the movement of the tonearm may be disturbed due to an erroneous operation at the start of horizontal movement of the tonearm. However, the tone arm can be guided to the correct performance start position without being affected by this. Additionally, since it uses a pulse motor, you can control the speed of the tone arm's movement simply by changing the pulse frequency.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention. FIG. 2 is a block diagram of the motor stop position detection circuit means. FIG. 3 is a block diagram of the motor signal circuit means. FIG. 4 is a block diagram of the plunger control circuit means. FIG. 5 is a block diagram of the rack circuit means. FIG. 6 is a time chart. 2...Start switch, 3...Flip-flop, 5...Control drive circuit, 7...Size detection switch, 11...Reference position detection sensor, 17...
Oscillator, 22...Motor stop position detection circuit,
25...Motor signal circuit, M...Pulse motor.

Claims (1)

[Scope of Claims] 1. A pulse motor driven by pulses from an oscillation circuit to horizontally move a tone arm from its armrest position to a record starting position; size detection means for detecting the size of the record; provided at one location within the movement range of the tone arm corresponding to a reference position set horizontally apart from the armrest position of the tone arm and corresponding to the size of the record detected by the size detection means; a reference position detection means for detecting that the tone arm has arrived at the reference position and outputting a detection signal thereof; and upon receiving the detection signal from the reference position detection means, it starts counting pulses from the oscillation circuit, and the count is a counter circuit that outputs a signal representing a value; and a pulse value to which the output signal of the counter circuit is input and corresponds to the amount of movement of the tone arm from the reference position to the performance start position of the record disc is preset. , motor stop control means for stopping the pulse motor when the count value of the counter circuit matches the pulse value.