JPH0224281Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a timer circuit suitable for use in a self-propelled record disc device.

Conventionally, record cleaners, static eliminators, and other self-propelled equipment for record discs have generally had a configuration in which they continue to self-propel on the record disc around the spindle of the player as soon as the power switch is turned on.
When stopping such equipment, the moving equipment must be picked up from the board in time with the rotation period of the equipment, making it difficult to handle and causing damage to the board.

To address this problem, some devices have a built-in timer that operates as soon as the switch is turned on and automatically shuts down after a predetermined period of time, but in all cases it is necessary to reset the timer after the device is turned off. However, such equipment is often used many times in a row, and if the operation becomes complicated, such as having to reset it each time, it is not only troublesome to handle, but it can also cause the equipment to become damaged due to incorrect switch operation on the record. There is also an increased risk of damaging the sound groove on the bottom wall.

This invention was made with attention to this problem, and the object is to provide a timer circuit that does not require a reset operation, is easy to handle, and has less fluctuation in timer time.

The present invention will be specifically described below based on embodiments shown in the drawings.

Although the drawings show an example in which the present invention is implemented in a static eliminator for record discs, the present invention is not limited to this, and it goes without saying that the present invention can be implemented in various self-propelled equipment for record discs, such as a record cleaner.

In Figures 1 to 3, 1 is a static eliminator implementing the present invention, 2 is a record support stand, 3 is a central shaft projecting upward from the support stand 2, and 4 is placed on the support stand 2. It's a record. The central shaft 3 passes through the center hole 5 of the record 4 and protrudes from the upper surface thereof, and the static eliminator 1 is placed and set on the record 4 which is horizontally supported.

The static eliminator 1 has a main body case 6 made of plastic formed in the shape of a long rectangular box along the radial direction of a record disc 4. A drive chamber 7 is formed at the base end of the case 6, and a discharge chamber 8 is formed at the distal end of the case. There is.

The drive chamber 7 houses a battery 9, a motor 10, and a speed reduction mechanism 11 including a gear group. A guide hole 13 into which the central shaft 3 is fitted is provided in the bottom surface 12 of the drive chamber 7, and a drive wheel 14 is supported at a position offset from the guide hole 13 toward the front end of the case so as to slightly protrude from the bottom surface of the case. This drive wheel 14 is in contact with the center side label portion 15 of the record disc 4 at its circumferential surface, and is rotationally driven by the motor 10 and the speed reduction mechanism 11, thereby causing the entire main body case 6 to rotate on its own.

The discharge chamber 8 is divided into two parts in the rotating direction by a separating wall 16 protruding from the bottom of the case, with a discharge electrode 17 on one side and a high voltage for applying a high voltage to the electrode 17 on the other side. A generating circuit 18 is provided. The discharge electrode 17 includes a plurality of needle electrodes 19, 19.
are arranged in the longitudinal direction at approximately equal intervals, with the tip 20 of each needle electrode 19 facing downward, and the lower surface facing the tip 20 facing the sound groove portion 2 of the record 4.
The opening has a narrow strip shape slightly longer than the width of 1, and forms an ion emitting port 22.

The present invention is characterized by a timer circuit 23 that regulates when to operate the drive section 36 such as the motor 10 and the high voltage generation circuit 18 described above.
As shown in FIG. 4, the timer circuit 23 has a first
2nd, 3rd, 4th inverter 24, 25, 26,
27, and at least the first and second inverters 24 and 25 are integrated in the same package, so that various electrical characteristics such as threshold values of each inverter are made equal. The output terminal c of the first inverter 24 and the input terminal e of the second inverter 25
is connected with capacitor C ₂ , and the second
Output end f of inverter 25 and first inverter 24
Connect input end b of with resistor _R1 . Furthermore, the capacitor
The DC voltage output from the battery 9 built into the static eliminator 1 is connected to the second inverter 25 side of C ₂ through a resistor R ₂
At the same time, the input end b of the first inverter 24 is applied through a normally open push button switch 31, which is provided on the upper wall 28 of the drive chamber 7 with its pressing piece 29 biased upward by a spring body 30. It is possible to instantaneously apply the voltage to the capacitor _C1 prepared for this purpose. Furthermore, the output signal 3 of the first inverter 24 is connected to the connection terminal a between the push button switch 31 and the capacitor _C1 .
2 is fed back through the third inverter 26. Output signal 32 from this first inverter 24
is simultaneously applied to the switching circuit 33 through the fourth inverter 27.

The switching circuit 33 includes transistors 34,
35 are connected in cascade, and a fourth inverter 27 is connected to the base end 37 of the transistor 34.
While applying the output signal of transistor 3
5 are connected in series to the motor 10 and the high voltage generating circuit 18, respectively. In a device that generates corona discharge like this embodiment, there is a possibility that the timer circuit 23 may malfunction due to residual sound or charges caused by ions.
The entire base of 3 is covered with a shield material 45 such as aluminum foil or tin foil, and this shield material 45 is connected to the cathode side of battery 9. Further, the pressing piece 29 is molded from a conductive material, and this pressing piece 29 is also used for the battery 9.
It is connected to the cathode side of the electrode via a lead wire 46.
47 is a capacitor for further preventing malfunction.

Next, the operation of the timer circuit 23 will be explained with reference to FIGS. 4 to 6.

In addition, FIGS. 6 a to 6 f respectively correspond to a shown in FIG. 4.
The voltage waveform at points ~f is shown.

As shown in FIG. 3, when the static eliminator 1 is set on the record 4, the power supply voltage _V1 is applied to the input terminal e of the second inverter 25 through the resistor _R2 , so the output terminal f is Low. Therefore, the input terminal b of the first inverter 24 becomes Low, and the output terminal c becomes Low.
Becomes High. This high signal is transmitted to the fourth inverter 2.
7, it is converted to a low signal, and the switching circuit 3
The input terminal d of No. 3 maintains the Low state, turns off the circuit 33, and does not energize the motor 10 and the high voltage generation circuit 18.

Here, at time t ₁ , the upper wall 2 of the main body case 6
When the press piece 29 exposed at 8 is pressed, the push button switch 31 inside the case is turned on momentarily. Then, the voltage V ₁ of the battery 9 is applied to the capacitor C ₁ , and the rise of the voltage V ₁ is differentiated by the capacitor C ₁ , and the input terminal b of the first inverter 24 becomes High.
change to the state.

At the same time, the output terminal c of the first inverter 24
Since the voltage is reversed to Low, a charging current flows from the battery 9 to the capacitor C ₂ through the resistor R ₂ . As the current flows through the resistor _R2 , a voltage drop due to the resistor _R2 causes the input terminal e of the second inverter 25 to
goes low momentarily, then as capacitor C ₂ and _{resistor R 2 charge}
The voltage gradually increases according to the time constant determined by the value of .

On the other hand, the output terminal c of the first inverter 24 is Low.
The signal is inverted by the third inverter 26.
At the same time, the voltage is applied to the capacitor C ₁ and changed to the High state by the fourth inverter 27, turning on the switching circuit 33 and turning on the motor 1.
0 and high voltage generating circuit 18 are activated. The driving wheel 14 rolls on the record 4 due to the operation of the motor 10, and the entire main body case 6 rotates around the central axis 3, and as shown in FIG. The tip 20 emits a corona discharge, and positive and negative ions 39 are generated by the discharge.
40, the electrostatic charge 4 charged on the record 4
1 and eliminates static electricity.

Here, the capacitor C ₂ is charged, and when the input voltage 42 of the second inverter 25 exceeds the threshold value V ₂ of the inverter 25 (time t ₂ ), the second inverter 25
is inverted and the output terminal f returns to the Low state. At the same time, current flows to capacitor _C1 , and the capacitor
The voltage 43 at the input terminal b of the first inverter 24 gradually decreases with a time constant determined by the values of C ₁ and resistor R ₁ .

Here, at time _t3 , the input voltage 43 of the first inverter 24 reaches the threshold value _V3 of the first inverter 24.
When the voltage at the output end c of the first inverter 24 is inverted from High to Low, the input signal 44 to the switching circuit 33 is also inverted to Low, turning off the switching circuit 33, and turning off the motor 10 and the high voltage. The operation of the generating circuit 18 is then stopped. Note that the above timer time t is determined by the resistance R ₁ and R ₂
and can be changed by changing the values of capacitors C ₁ and C ₂ . At this time, if the threshold values V ₃ and V ₂ of the first and second inverters 24 and 25 and the values of the resistors R ₁ and R ₂ and the capacitors C ₁ and C ₂ are respectively set equal, the timer time t becomes t. = −R ₁ C ₁ [ln{(V ₁ −V ₂ )/V ₁ } +ln(V ₂ /V ₁ )], and the fluctuation of the power supply voltage V ₁ is expressed by the first and second terms in the above equation. Therefore, regardless of fluctuations in the power supply voltage _V1 , fluctuations in the timer time t can be suppressed to the necessary minimum.

In addition, if the static electricity removal by the static eliminator 1 is insufficient,
By simply pressing the pressing piece 29 of the push button switch 31, the above-described operation is repeated, and then the initial state is returned.

As mentioned above, although the timer circuit 23 according to the present invention has a relatively simple configuration, it does not require any troublesome operations such as resetting operations, and can be started, stopped, and initialized simply by pressing the push button switch 31. Since the operation is configured to complete automatically, it is easy to handle, anyone can operate it without making mistakes, and it has the effect of preventing accidents in which the bottom wall of the equipment used damages the record surface.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an example of the present invention with the upper case removed, Fig. 2 is a sectional view taken along the line shown in Fig. 1, and Fig. 3 is a perspective view showing the state of use. It is. FIG. 4 is a circuit diagram of a timer circuit according to the present invention, FIG. 5 is an explanatory diagram showing a static elimination state, and FIGS. 6 a to 6 f are waveform diagrams illustrating operating conditions of the timer circuit. 1...Static eliminator, 4...Record, 9...Battery, 10...Motor, 18...High voltage generation circuit,
23... Timer circuit, 24... First inverter, 25... Second inverter, 26... Third inverter, 27... Fourth inverter, 28... Drive chamber upper wall, 29... Pressing piece, 31... ...Push button switch, 33...Switching circuit.

Claims (1)

[Claims for Utility Model Registration] (1) The output terminal c of the first inverter 24 and the input terminal e of the second inverter 25 are connected by a capacitor _C2 ,
Output end f of inverter 25 and first inverter 2
4 are connected through resistors _R1 , and the output voltage of the built-in DC power supply 9 is connected to the first inverter 2.
A normally open push button switch 3 is connected to the input end b of 4.
A resistor is connected to the input terminal e of the second inverter 25 via a series connection of capacitor C1 and capacitor _C1 .
The signal 32 applied via R ₂ and taken out from the output terminal c of the first inverter 24 is
At the same time, the voltage is applied to the connection terminal a of the push button switch 31 and the capacitor C1 via the third inverter ₂₆ , and at the same time, the switching circuit 33 of the drive unit 36 is applied.
A timer circuit for a self-propelled device for record discs, which is input as a control signal. (2) The capacitors C ₁ and C ₂ and the resistors R ₁ and R ₂ have approximately the same value, and the first and second inverters 24 and 25 have the same electrical characteristics as claimed in claim 1 of the utility model registration. Timer circuit as described. (3) The timer circuit according to claim 1 or 2, wherein the push button switch 31 has a pressing piece 29 on the upper side of the rotation center of the self-propelled device 1.