JPS6138081Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an arm braking device for a player that prevents the arm from turning unexpectedly.

As is well known, the arm of the player is constructed so that it can always rotate horizontally around its support so that the stylus of the pick-up cartridge can move to follow the recording groove of the record. . By the way, the arm configured in this manner has a problem in that the arm is always in a state where it can rotate in the horizontal direction, and the arm may unexpectedly rotate at times other than when tracing a record.
In other words, the arm is usually subjected to a reaction force due to twisting of the lead wire and an external force due to an inside force canceller, and if these act on the arm during the arm's upward and downward movements, the arm will become fixed. There is an inconvenience that it becomes impossible to ascend or descend to a certain position. This problem becomes a major problem when the arm is lowered, especially when the lead-in position of the arm is shifted, as it interferes with the performance of the record.

This idea was made in view of the above-mentioned circumstances, and was designed to provide resistance to the horizontal rotation movement of the arm, especially during the downward movement of the arm, thereby eliminating the above-mentioned disadvantages. The present invention provides a brake device for an arm in a player.

That is, the brake device of this invention includes an arm lifter, a cueing solenoid that operates the arm lifter so that the arm lowers, and
The brake mechanism includes a brake mechanism that applies resistance to horizontal rotational movement of the arm, a brake solenoid that drives the brake mechanism, and a control circuit that drives and controls the cueing solenoid, and both of the solenoids are controlled by the control circuit. The control is performed based on an arm lowering command signal issued from the arm lowering command signal. In one aspect of the invention, the brake device is provided with means for connecting both of the solenoids so that a drive voltage is applied to them in parallel, and applying a predetermined amount of reverse bias to the brake solenoid. It is.

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

The drawing shows an embodiment in which this invention is applied to a brake equipped with a linear tracking arm. In FIG. show. This arm device 1 has an arm 3 (pickup arm) having a pickup cartridge 3a mounted on a support base 2 so as to be rotatable in vertical and horizontal directions, and the arm 3 is moved up and down by an arm lifter 4. When driven by a drive control circuit to be described later, the arm 3 is positioned in the tangential direction of the recording groove of the record disc a, and the arm 3 moves linearly in the directions of arrows A and B. It is starting to move to . The detailed structure of this arm device 1 is as shown in FIG. That is, this arm device 1
The arm 3 has its base end fixed to the first arm support 5a. The first arm support 5a is connected to a second arm support 5b having a U-shaped cross section.
is supported so as to be rotatable about a horizontal axis. Also, the second arm support 5b
is supported so as to be rotatable about a vertical shaft 6 attached to the support base 2. Based on such a configuration, the arm 3 is vertically rotatable with respect to the support base 2 together with the first arm support 5a, and the arm 3 is rotatable in the vertical direction with respect to the support base 2.
It is also horizontally rotatable about the shaft body 6. Further, the arm lifter 4 has a U-shaped cross section having a lower wall portion 7 and side wall portions 8, 8. It is supported so that it can rotate in the direction. However, when the lever arm lifter 4 is rotated about the axis, the arm support wall 9 formed at the front end of the lower wall 7 supports a pin provided on the first support 5. 10 is moved up and down, and the arm 3 is moved up and down. The support base 2 is also provided with a cueing solenoid 11 and a spring 12 for rotating the arm lifter 4, and a damper device 13 that provides a damping effect to the rotational movement of the arm lifter 4. In other words, the cueing solenoid 1
1 is arranged so that the tip end surface of the plunger 14 can come into contact with the rear surface of the protruding wall 15 formed at the rear end of the lower wall 7, and the main body 16 is attached to the wall 2a of the support base 2. Fixed. Further, the spring 12 has a pin 1 implanted in a fixing part 17 formed at the tip of the plunger 14 and the lower wall part 7 in order to pull out the plunger 14 in the direction of arrow E.
8, and extends through a slit 19 formed in the protruding wall portion 15. The damper device 13 is constructed by inserting a piston rod 21 into an oil dump cylinder 20.
2 are engaged in grooves 24, 24 of an engaging wall portion 23 formed on the lower wall portion 7, and the oil dump cylinder 20 is fixed to the wall portion 2b of the support base 2. However, the damper device 13 provides a damping effect to the operation of the arm lifter 4 by a buffer mechanism inside the oil dump cylinder 20, but on the other hand, it is fixed to the front end surface of the oil dump cylinder 20 and the tip of the piston rod 21. ring 2
The arm lifter 4 is biased in the direction of the arrow E by a spring 26 interposed between the arm lifter 5 and the arm lifter 5.

In the arm device 1 having such a configuration, when the arm 3 is in the raised position, the rod 21 of the damper device 13 is pulled out in the direction of the arrow E by the spring 26, so that the arm lifter 4
The arm 3 is held in the raised position by the arm support wall 9 holding the pin 10 in the raised position. When the arm 3 is to be lowered, the queuing solenoid 11 is energized to move the plunger 14 in the direction of the arrow F. That is, when the plunger 14 moves in the same direction, the arm lifter 4 rotates in the direction of the arrow C via the spring 12, whereby the pin 10 follows the arm support wall 9 of the arm lifter 4 and descends, thereby lowering the arm 4. When the arm 3 is to be raised, the energization of the queuing solenoid 11 is released. That is, when this release is performed, the piston rod 21 moves in the direction of the arrow E due to the biasing force of the spring 26, and the arm lifter 4 moves in the direction of the arrow E accordingly.
The arm 3 rotates in the direction of the arrow D, whereby the arm support wall 9 raises the pin 10, and thus the arm 3
In this raising and lowering operation of the arm 3, the damper device 13 provides a buffering effect to the movement of the arm lifter 4, thereby allowing the arm 3 to rise and fall smoothly.

Further, in the arm device 3, a mounting plate 30 is fixed to the rear end of the piston rod 21 of the damper device 13 that projects rearward from the oil dump cylinder 20, and a magnet 31 is attached to the mounting plate 30. A reed switch 32 (magnetic sensitive element) is disposed below the damper device 13 so as to face the magnet 31 when the arm 3 is in the raised position. This reed switch 32 is turned on when the piston rod 21 of the damper device 13 moves in the direction of arrow E and the magnet 31 reaches the position shown by the two-dot chain line in the figure.
is in the raised position.

Further, below the arm lifter 4, there is provided an arm deviation angle detection mechanism 40 that detects the horizontal deviation angle of the arm 3 when the arm 3 rotates in the horizontal direction according to the trace on the record. It is being That is, the base of a fan-shaped shutter plate 41 having a hole 41a in the center is fixed to the lower end of the shaft 6. Furthermore, a light emitting diode 42 and a phototransistor 43 are provided above and below the shutter plate 41, respectively. Based on this configuration, the arm deflection angle detection mechanism 40 is configured such that the light emitting diode 42 illuminates the phototransistor 43 through the hole 41a of the shutter plate 41, and when the shutter plate 41 rotates (the arm 3 is phototransistor 43 (when rotated)
The device is configured to detect the deflection angle of the arm 3 according to the amount of light received by the arm.

Further, a brake mechanism 45 is provided below the arm lifter 4 to provide resistance to the horizontal rotational movement of the arm 3 when the arm 3 is lowered. This brake mechanism 45 is constructed using the shutter plate 41 and is constructed as follows. That is, the shutter plate 4
A brake arm 46 is disposed above the shutter plate 41 so as to extend in a direction substantially perpendicular to the direction in which the shutter plate 41 projects. A brake plate 47 is fixed to a substantially central portion of the brake arm 46 so as to face the front edge 41b of the shutter plate 41. And the brake arm 46 is
A portion near one end thereof is rotatably attached to a fixing pin 48 disposed on the side of the shutter plate 41. Further, this brake arm 46 is always moved in the direction of arrow G about the pin 48 by a spring 52 stretched between a hole 49 formed at one end thereof and a pin 51 implanted in the fixed plate 50. energized. In this case, the fixed plate 50 is fixed to the wall 2C of the support base 2. Further, behind the other end of the brake arm 46 is a brake solenoid 5 that drives the brake mechanism 45 having the above-mentioned configuration.
3 are arranged. This brake solenoid 53 has a main body 54 fixed to the wall 2d of the support base 2, and a tip of the plunger 55 connected to the pin 5.
6 to the other end of the brake arm 46. Further, an eccentric cam 57 is provided on the other end side of the brake arm 46 so as to come into contact with the front end edge 46a of the brake arm 46. The eccentric cam 57 is rotatably attached to a fixed pin 58 and comes into contact with the brake arm 46 to restrict rotation of the arm 46 in the direction of arrow G. With this configuration, when the brake solenoid 53 is driven and the plunger 55 is attracted in the direction of the arrow I, the brake arm 46 rotates in the direction of the arrow H about the pin 48, and the brake plate 47 is activated by the shutter. Front edge 41 of plate 41
b, so as to provide resistance to the rotational movement of the arm 3 in the horizontal direction. In this case, the amount of offset of the brake plate 47 is adjusted by rotating the eccentric cam 57.

Also, Fig. 3 shows the arm 3 in this player.
FIG. 2 is a diagram showing a drive control circuit. In this figure, solid line arrows indicate electrical signal transmission lines, and broken line arrows indicate power transmission lines. In this figure, numerals 60a to 60c are lead-in command buttons for leading in the arm 3 according to the diameter of the record, 60d is a repeat button for issuing a command for repeat playback of the record, and 60e is a cutting operation of the arm 3. This is the cut button. Also code 61
are the buttons 60a to 60c and the comparison output detection circuit 6.
2. Based on the signals supplied from each part of the final groove detector 63, the voltage Va is supplied to the comparator 64, and the arm raising/lowering command signal Ve [the high level signal shown in FIG. 4a] is sent to the solenoid drive circuit 65. This is a control circuit that supplies a signal consisting of a low level signal (hereinafter referred to as an H signal) and a low level signal (hereinafter referred to as an L signal). In this case, the voltage Va is a voltage corresponding to the position of the arm 3 in the directions of arrows A and B, and corresponds to the lead-in position according to the diameter of the record when the lead-in command buttons 60a to 60c are operated, for example. The voltage will be The comparator 64 compares the voltage Va
and the output voltage Vb of the arm position detector 66 that detects the position of the arm 3 in the directions of arrows A and B,
The comparison output Vr is supplied to the motor drive circuit 68 via the changeover switch 67 and also to the comparison output detection circuit 62. The motor drive circuit 68 receives the output Vr of the comparator 64 via the changeover switch 67.
Alternatively, the motor 70 is rotated based on the output Vs of the arm deflection angle detection mechanism 40, thereby moving the arm device 1 in the direction of arrow A or B. In this case, the arm deflection angle detection mechanism 40 detects that when the arm 3 traces the record a, the stylus of the pick-up cartridge 3a reaches the record a.
It detects the deviation angle that occurs when the recording groove is moved, and the voltage Vs corresponding to the deviation angle is detected.
This outputs the following. Further, the comparison output detection circuit 62 detects that the voltage Vr becomes zero, and supplies the detection signal Vc to the control circuit 61. Further, the final groove detector 63 detects the pickup cartridge 3 after the record playback is completed.
It detects when the tip of the stylus a reaches the lead-out groove (the final end of the recording groove) of the record a, and supplies the detection signal Vd to the control circuit 61. Control circuit 61
supplies an H signal serving as an arm lowering command signal to the solenoid drive circuit 65 when receiving the detection signal Vc, supplies an L signal when receiving the detection signal Vd, and lowers the voltage Va. Switch to the voltage corresponding to the armrest position. Further, this control circuit 61 controls the voltage Va to be input to the lead-in command button 6 when the repeat button 60d is operated.
The solenoid drive circuit 6 is fixed to the values set in 0a to 60c, and when the cut button 60e is operated
The L signal is supplied to 5. Further, when the solenoid drive circuit 65 receives the arm raising/lowering command signal Ve, the solenoid drive circuit 65 generates a signal shown in FIG. 4b, that is, a signal Ve.
A signal Vo is output which maintains a voltage equal to or higher than the voltage Ea (V) for a predetermined time from the rise of the voltage Ea (V), and then gradually decreases to a voltage lower than the Ea (V) and maintains the voltage Eb (V) as long as the signal Ve is an H signal. Further, the output Vo of the solenoid drive circuit 65 is applied to the cueing solenoid 11 and the brake solenoid 53, respectively. In this case, the solenoids 11 and 53 are connected so that the drive voltage Vo is applied in parallel to them. That is, the solenoid drive circuit 6
A solenoid 11 is connected between the output end of the solenoid 5 and the ground point, and a solenoid 11 is connected between the output end and the ground point of the solenoid 5.
3 and a Zener diode 71 are connected in series. At this time, the Zener diode 71 is
This constitutes means for applying a predetermined amount of reverse bias to the solenoid 53. Based on this configuration, solenoid 1
1, 53 is the output Vo of the solenoid drive circuit 65
driven by. In this case solenoid 11
is driven through the time t ₁ shown in FIG. 4b.
Further, since a reverse bias is applied to the solenoid 53 by the Zener diode 71, the solenoid 53 is driven only during a time period _t2 in which the voltage of the output Vo is equal to or higher than Ea. Here, the time t ₂ is set to the time during which the arm 3 moves downward, and this time is determined by the Zener voltage of the Zener diode 71.

Thus, as described above, the arm lifter 4 lowers the arm 3 when the solenoid 11 is driven, and raises the arm 3 when the drive is released. At this time, when arm 3 descends,
When the solenoid 53 is driven, the brake mechanism 45 operates, and resistance is applied to the rotational movement of the arm 3 in the horizontal direction. Further, the damper device 13 interlocked with the movement of the arm lifter 4 changes the position of the magnet 31 depending on the vertical position of the arm 3, thereby turning the reed switch 32 on/off. The on/off signal of the reed switch 32 is then supplied to the changeover switch control circuit 72. The changeover switch control circuit 72 turns on/off the transistor 73 based on the on/off signal of the reed switch 32, thereby controlling the operation of the solenoid 74 to change over the changeover switch 67. In this case, the changeover switch 67 has its movable contact 67a in contact with the contact 67b when the reed switch 32 is on, and contacts the contact 67c when the reed switch 32 is off.
contact the side.

Next, the operation of the player with the above configuration is as follows.
The details will be explained using an example of automatically playing a 30cm record.

First, it is assumed that the arm 3 is at the armrest position when starting to play the record. In this state, the movable contact 67a of the changeover switch 67 of the drive control circuit shown in FIG. 3 is in contact with the contact 67b since the arm 3 is in the raised position and the reed switch 32 is in the on state. When the lead-in command button 60a for the 30 cm record is operated, the control circuit 61 outputs a voltage Va corresponding to the lead-in position of the 30 cm record, and supplies this to the comparator 64. Comparator 64
compares the voltage Va and the voltage Vb corresponding to the current position of the arm 3 supplied from the arm position detector 66, and obtains a comparison voltage Vr=K(Va−Vb>O
(where K is a positive constant) is output. The positive output voltage Vr of this comparator 64 is supplied to a motor drive circuit 68 via a changeover switch 67. The motor drive circuit 68 causes the motor 70 to rotate forward based on the output voltage Vr, thereby moving the arm device 1 in the direction of arrow A. When arm 3 reaches the lead-in position of the 30cm record, the voltage
Va matches the voltage Vb, and the output voltage Vr of the comparator 64 becomes zero. As a result, the motor drive circuit 68
stops the rotation of the motor 70 and stops the movement of the arm device 1. On the other hand, comparison output detection circuit 62
detects that the output voltage Vr has become zero, and supplies the detection signal Vc to the control circuit 61. The control circuit 61 supplies an H signal to the solenoid drive circuit 65 based on the detection signal Vc.
As a result, the solenoid drive circuit 65 outputs the output Vo, the solenoid 11 is driven, the arm lifter 4 rotates as described above, and the arm 3 descends.
The stylus tip of the pick-up cartridge 3a is then introduced to the starting end of the recording groove of the record a. At this time, the output is only during the period when arm 3 moves downward.
The solenoid 53 is driven by Vo, the brake mechanism 45 is operated, and resistance is applied to the rotational movement of the arm 3 in the horizontal direction. Thus, when the arm 3 moves downward, the arm 3 is prevented from rotating unnecessarily in the horizontal direction, and an accurate lead-in operation is performed. At this time, since the rod 21 of the damper device 13 moves in the direction of the arrow F, the magnet 31 separates from the reed switch 32, turning the reed switch 32 off. As a result, the changeover switch control circuit 72 turns off the transistor 73, de-energizes the solenoid 74, and turns off the changeover switch 67.
Switch the movable contact 67a to the contact 67c side. After the arm 3 has been lead-in in this way, the arm device 1 detects the output of the arm deflection angle detection mechanism 40.
Driven based on Vs. In other words, arm device 1 moves arm 3 along with tracing of record a.
is moved in the direction of arrow A so that this deviation is corrected.

Further, the arm 3 auto-returns as follows when the reproduction of the record a is completed.
That is, when the tip of the pick-up cartridge 3a reaches the final end of the recording groove of the record a, this state is detected by the final groove detector 63, and this detection output Vd is supplied to the control circuit 61. The control circuit 61 supplies an L signal to the solenoid drive circuit 65 based on the output Vd. As a result, the solenoid drive circuit 65 de-energizes the solenoid 11 . Also, at this time, the output voltage of the control circuit 61
Va is switched to a voltage corresponding to the armrest position. As a result, the arm lifter 4 rotates and the arm 3 rises, and the piston rod 21 of the damper device 13 moves in the direction of arrow E, so that the magnet 31 faces the reed switch 32, and the reed switch 32 is turned on. Become. As a result, the changeover switch control circuit 72 turns on the transistor 73, the solenoid 74 operates, and the movable contact 67a of the changeover switch 67 is switched to the contact 67b side. Here, the comparator 64 compares the voltage Va corresponding to the armrest position with the voltage Vb corresponding to the current position of the arm 3, and outputs a voltage such that Vr=K(Va−Vb)<O. A negative output voltage Vr is supplied to the motor drive circuit 68. The motor drive circuit 68 is
The motor 70 is reversely rotated based on the negative voltage Vr, thereby moving the arm device 1 in the direction of arrow B. When the arm 3 reaches the armrest position, the Vb matches the Va and the output voltage Vr of the comparator 64 becomes zero, causing the motor drive circuit 68 to stop the rotation of the motor 70 and turn the arm device 1 stop moving. Note that when the arm 3 is in the armrest position, a control circuit (not shown) puts the comparison output detection circuit 62 in a non-operating state,
Arm 3 is held in the raised position.

The above embodiment is an example in which this invention is applied to a player equipped with a linear tracking arm. However, the application of this invention is not limited to players with linear tracking arms, but can also be applied to players with rotating arms. When this invention is applied to a player having a rotating arm, it is preferable to use a shutter plate for detecting the final groove of a record as the shutter plate used in the brake mechanism.

As is clear from the above explanation, according to this invention, resistance is applied to the horizontal rotation movement of the arm during the downward movement of the arm. Rotation can be prevented, and the lead-in operation of the arm can be performed accurately.

[Brief explanation of drawings]

Figure 1 is a plan view of the main parts of a player equipped with a linear tracking arm to which this invention is applied;
The figure is a perspective view of the main parts of the arm device 1 shown in FIG. 1, FIG. 3 is a block diagram showing the main part configuration of the drive control circuit of the arm device 1, and FIG. 4a is the drive control circuit shown in FIG. 3. The signal Ve output from the control circuit 61 of
FIG. 4b is a waveform diagram of the signal Vo output from the solenoid drive circuit 65 of the same drive control circuit. 1...Arm device, 3...Arm, 4...Arm lifter, 11...Kueing solenoid,
45... Brake mechanism, 53... Brake solenoid, 61... Control circuit, 65... Solenoid drive circuit.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) An arm lifter, a cueing solenoid that operates the arm lifter to lower the arm, a brake mechanism that provides resistance to horizontal rotation of the arm, and this brake mechanism. and a control circuit that drives and controls the cueing solenoid, and controls the cueing solenoid and the brake solenoid based on an arm lowering command signal issued from the control circuit. A brake device for an arm in a player made as follows. (2) Registration of a utility model in which the queuing solenoid and the brake solenoid are connected so that a drive voltage is applied to them in parallel, and a means is provided for applying a predetermined amount of reverse bias to the brake solenoid. A brake device for an arm in a player according to claim 1.