JPS6316807B2 - - Google Patents

Description

[Detailed Description of the Invention] The size of the record placed on the turntable is automatically determined, and the playback needle is automatically lowered to the lead-in position of the record, so that the record is automatically played. Various types of automatic record players have been proposed in the past, but in the automatic record players that have been proposed so that the record size is determined by an optical sensor, For example, the turntable may be configured so that its surface has a high light reflectance so that the size of the record can be determined by the reduction in the amount of reflected light incident on the light receiving element of the optical sensor. This method was used to determine whether the record placed on the turntable blocked the light passing through the transparent hole by electrically detecting whether the record was transparent or not. If it had been created, automatic performance would not have been possible.

The present invention is applicable to the record whether it is opaque to light or transparent to light.
An automatic record player that automatically determines the record size so that automatic playback can be performed without any problem regardless of the record size, that is, the tone arm can be rotated horizontally. an address signal generator that generates an address signal corresponding to the horizontal rotation angle of the tone arm, and an address signal generator that generates an address signal that corresponds to the horizontal rotation angle of the tone arm. It is attached to the tone arm at a position that draws a movement trajectory that approximately matches the arc-shaped movement trajectory drawn by the tip of the playback stylus, and is located closer to the inner circumference of the record than the cartridge installation position. It has a light-emitting element and a light-receiving element, and has an optical sensor that detects the state of light reflection on the turntable surface or record surface, and stores an address signal corresponding to the lead-in position for each record size, and also stores the corresponding lead-in position. Control for determining the rotation angle of the tone arm at lead-in for each record size by comparing the address signal corresponding to the lead-in position of the record size with the address signal obtained from the address signal generator described above. Among the reflected light emitted from the light emitting element to the reflective surface in the optical sensor, the amount of light reaching the light receiving element in the optical sensor is determined by the position and the amount of light that reaches the light receiving element in the optical sensor. a turntable having a surface with fewer grooves than a surface without grooves, and a state in which the tone arm is rotated from the outside of the turntable toward the center of the turntable; If records of various sizes are placed on a turntable, the signal level of the output signal obtained from the optical sensor is expected to be at the outer periphery of the record placed on the turntable. When the tone arm indicates a signal level above a certain signal level near the area, or near the area expected to be occupied by the outer periphery of the record placed on the turntable, the tone arm moves inside the turntable. When a record of the corresponding size is placed on the turntable when it shows a state of attenuation exceeding a predetermined signal level while moving in that direction, the record of the corresponding size is The purpose of this invention is to provide an automatic record player that automatically determines the record size and starts playing by guiding the tone arm so that the playback needle is positioned at the standard lead-in position on the record. be.

Hereinafter, specific details of the automatic record player that automatically determines the record size of the present invention will be explained in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a schematic configuration of an automatic record player that automatically determines the record size according to the present invention. In FIG. 1, HM is a horizontal block for horizontally rotating the tone arm 1. Also, VM is a vertical drive motor for vertically rotating the tone arm, and AC is the two drive motors HM,
This arm control circuit AC provides a drive signal to VM, and its operation is controlled by the control device CD, and also provides information regarding the state of the tone arm 1 to the control device CD.

AE is an address signal generator (arm angle encoder) that generates an address signal corresponding to the horizontal rotation angle of tone arm 1, and the output from this arm angle encoder AE is sent to the control device.
Given to CD. Also, TM is the turntable drive motor, MC is the motor control circuit, MS is the muting switch, KM is the key matrix, DP is the display device, and PS is the optical sensor.This optical sensor PS is connected to the tone arm. It is provided separately from the head shell and consists of a light source and a light receiving element, and this is because the tip of the regeneration needle of the cartridge attached to the head shell attached to the tone arm is connected to the tone arm. It is possible to draw a rotational trajectory that is almost the same as the rotational trajectory drawn when rotating, and it can also be positioned slightly ahead of the head shell attached to the tonearm in the direction of movement of the tonearm when playing a record. It is connected and fixed to the tone arm so that it is in the same position as the tone arm.

SPS is a stylus position correction signal generation circuit, SP is a stylus pressure adjustment signal generation circuit, and each of these circuits
SPS, SP, etc. can be configured with variable resistors each connected to a voltage source with a constant voltage, and in this case, the needle position correction signal, needle pressure adjustment signal, etc. It can be taken out from the slider of another variable resistor.

Further, AMP is an amplifier that amplifies the above-mentioned stylus force adjustment signal and supplies it to the vertical drive motor VM.

The aforementioned optical sensor PS and needle position correction signal generator
Various information signals generated from the SPS, stylus force adjustment signal generation circuit SP, etc. are sent to the control device CD
transfer switch whose switching state is controlled by
It is individually given to the AD converter ADC via SW. The output from the AD converter ADC is then supplied to the control device CD.

The control device CD includes a microprocessor, random access memory (RAM), read-only memory (ROM), etc., and this control device CD receives information signals (for example, playback) input from the key matrix KM. , reservation of song number,
end, other information), an information signal related to the arm status input from the arm control circuit AC, an information signal indicating address information input from the arm angle encoder AE, and an information signal input from the motor control circuit MC. The information signal regarding the rotation angle of the turntable to be rotated, as well as various information generated by the optical sensor PS, needle position correction signal generation circuit SPS, stylus pressure adjustment signal generation circuit SP, etc., are AD converted by the AD converter ADC.
When receiving a converted information signal, etc., each component is controlled so that each predetermined component can perform a required operation, as will be described later.

FIG. 2 is a perspective view showing a schematic configuration of an example of arm angle encoder AE, and in FIG. 2, 1 is a tone arm, and 2 is a tone arm 1.
A shaft 3 rotates integrally with the tone arm 1 when the tone arm 1 rotates in the horizontal direction, and 3 is a code plate fixed to the shaft 2. A row of through holes 3a, 3a, . . . showing different cords are bored radially from the center of the shaft 2, which is the center of rotation in the rotational movement. Further, in FIG. 2, reference numerals 4 and 5 denote a light source array 4 and a photoelectric conversion element array 5, which are provided at opposite positions with the code plate 3 interposed therebetween. and the code plate 3 constitute an arm angle encoder AE.

In other words, each of the plurality of light sources forming the light source array 4 and the individual light sources of the plurality of photoelectric conversion elements forming the photoelectric conversion element array 5 are each specific light source. and each specific photoelectric conversion element are arranged in such a manner that they correspond to each other, and are arranged toward the center of rotation of the tone arm 1 in the horizontal direction,
Further, as described above, the code plate 3 fixed to the shaft 2 that rotates as the tone arm 1 rotates in the horizontal direction between the light source array 4 and the photoelectric conversion element array 5 is Since the through hole rows 3a, 3a, . In this case, the through-hole rows 3a, 3a, . . . showing different codes depending on the rotation angle are located between the light source row 4 and the photoelectric conversion element example 5, and therefore,
The level of the output signal from each photoelectric conversion element in the photoelectric conversion element row 5 is selected by the level detection circuit, and the signal is made into a signal of a different code depending on the rotation angle of the tone arm 1 in the horizontal direction. be.

Arm angle encoder illustrated in Figure 2
In AE, the code plate 3 is rotated together with the shaft 2, and the light source array 4 and the photoelectric conversion element array 5 are fixedly provided at fixed positions. 5 may be rotated together with the shaft 2, and the code plate 3 may be fixedly provided at a fixed position.

As mentioned above, the arm angle encoder AE generates signals of different codes depending on the horizontal rotation angle of the tone arm 1 with the axis 2 as the rotation center.
The output signal from the tone arm 1 can be an address signal indicating the address in the horizontal direction of the position that the tone arm 1 occupies in space when the tone arm 1 is displaced in the horizontal direction by rotational movement, and , it can be an address signal indicating the address in the horizontal direction of a specific point set on the tone arm 1 or a point placed in a unique positional relationship with respect to the specific point set on the tone arm 1. be.

Therefore, the position of the tip of the regeneration needle S of the cartridge 7 attached to the head shell 6 to be attached to the tone arm 1 is determined by which head shell 6 among the plurality of head shells to which different cartridges are attached. Even when mounted on the arm 1, if the distance in the horizontal direction between the tone arm 1 and the specific point always shows a constant value, then the above-mentioned arm angle encoder AE The output signal can be used as an address signal for the position of the tip of the regenerating needle S, but in reality, by replacing the head shell when replacing the cartridge,
Since it is normal for there to be some deviation in the positional relationship between the tip of the playback needle S of the cartridge and the specific point set on the tone arm 1, the output signal from the arm angle encoder AE is It cannot be used as an address signal indicating the address of the tip position of the regenerating needle or the position corresponding to the tip position of the regenerating needle.

However, in order to ensure that the positional relationship with the specific point set on the tone arm 1 remains unchanged even when the head shell is replaced when replacing the cartridge, a light sensor separate from the head shell 6 is provided.
The PS is connected and fixed to the tone arm 1 by the connecting part 8 as shown in Fig. 3, and the position of the optical sensor PS (this can be considered as the horizontal position of the position detection point by the optical sensor PS) The correspondence relationship between the address of the head shell 6 and the address signal indicated by the output signal of the arm angle encoder AE mentioned above is
The address of the position of the tip of the regenerated needle S, which changes due to replacement of the head shell 6, etc., can be easily set based on the address of the optical sensor PS described above. If the head shell 6 is replaced, even if the positional relationship between the needle tip position of the regenerated needle S and a specific point on the tone arm 1 changes, the regenerated needle S This makes it possible to easily obtain an address signal indicating the address of the needle tip position.

By replacing the head shell 6, etc., the regenerated needle S
If the positional relationship between the needle tip position and the specific point set on tone arm 1 changes, tone arm 1
To easily correct the address of the tip of the regenerated needle S based on the address corresponding to the position of the optical sensor PS, which is always provided in a fixed positional relationship with a specific point set in , tone arm 1
corresponds to the horizontal position of the tip of the regenerating needle S and the horizontal position of the position detection point by the optical sensor PS, respectively, within a predetermined rotation range when the regenerating needle S rotates in the horizontal direction. It is required that the difference in addresses in the radial direction of the turntable be constant or approximately constant.

For this purpose, the optical sensor PS, which should be connected and fixed to the tone arm 1, produces a tone whose movement trajectory is approximately the same as the arc-shaped movement trajectory drawn by the tip of the playback needle S when the tone arm 1 rotates in the horizontal direction. Arm 1
A position that can be drawn by the movement of the detection point by the optical sensor PS when rotating in the horizontal direction, and is ahead of the tone arm 1 in the direction in which the tone arm 1 advances when playing a record. The tone arm 1 is connected and fixed to the tone arm 1 in such a manner that it is juxtaposed with the head shell 6 on the opposite side.

As shown in the longitudinal sectional front view in FIG. 3, the optical sensor PS includes a light shielding plate 11 (partition wall 11) and a case 10 which is connected and fixed to the tone arm 1 by a connecting part 8. Light source 12 and light receiving element 13
The light emitted from the light source 12 is reflected by the reflective surface, and the light is received by the light receiving element 13 to obtain an electrical signal according to the state of the reflective surface. ing.

Figure 4a shows the reflection path of light in a state where the light emitted from the light source 12 of the optical sensor PS is irradiated onto the groove g of the record D, and the reflection path of the optical sensor PS.
The light emitted from the light source 12 hits the groove g of the record D.
This diagram illustrates and explains the reflection path of light when it is irradiated onto parts other than the recording part (the non-recorded part on the outer periphery of the record D, the band between songs, the turntable surface, etc.), and FIG. As shown in the figure, when the light is irradiated onto the groove g of the record, only a small amount of reflected light reaches the light receiving element 13, and the light does not reach the groove g of the record. When a part other than the part is irradiated, a large amount of reflected light reaches the light receiving element, and therefore the detection power obtained from the light receiving element 13 is the same as that of the light irradiated from the light source 12 of the optical sensor PS. The resulting light changes as shown in FIG. 4B, depending on whether the emitted light hits the non-recorded part or the groove part of the surface of the record D.

Fig. 4b shows that the light irradiated from the light source 12 of the photosensor PS creates a spot on the reflective surface that is large enough to include a plurality of grooves in the record D. This figure illustrates and explains the difference in the detection power of the optical sensor PS when the light from the light source 12 of the sensor PS hits the groove part of the record D and when it hits the non-recorded part. In Figure 4b,
The detection force shown in each part A, C, and E corresponds to the part where the groove g of the record D exists, and the optical sensor
There is a detection power output from PS, and
The detection power in each part of D and F is record D.
The detection power of the optical sensor PS corresponding to the unrecorded part in is shown.

By the way, in automatic record players,
In order to determine the size of the record placed on the turntable T and to be played, and to ensure that the lead-in is always performed in the correct state regardless of the size of the record. It is necessary to detect the outer edge of the turntable T, but in order for this detection to be performed by the optical sensor PS, the turntable T must be illuminated with light from the light source 12 of the optical sensor PS. If there is no discernible difference between the detection power from the optical sensor PS in the state in which the light from the light source 12 of the optical sensor PS illuminates the non-recorded part of the outer periphery of the record, No.

In the already proposed automatic record player (for example, Japanese Patent Application No. 54-70940), a turntable T whose surface has a high light reflectance is used, and the tone arm 1 is connected to the turntable T. When the turntable T is moved from the outside toward the center of the turntable T, the detection force of the optical sensor PS shows a very high signal level in the exposed part of the turntable T, and also shows a very high signal level in the exposed part of the turntable T. In the previous proposal, the lowering of the signal level was used to determine the edge position of the record and the size of the record.In this case, the record was opaque and reflected light. When a surface with a low surface condition is used, the edge of the record can be determined without any cracks by the detection power of the optical sensor PS, but the record placed on the turntable T. The surface of the turntable T has an extremely high light reflectance, and the amount of light reflected from the record surface is large, or the record is transparent, and as a result, the light reflected from the surface of the turntable T is reflected from the record surface. In cases where even the existing portion is applied to the light receiving element of the optical sensor PS, it becomes difficult to distinguish the edge of the record in a good condition, causing a problem that automatic performance is hindered.

Therefore, in the present invention, in the turntable T on which a record is placed, the amount of light that reaches the light receiving element in the optical sensor PS, out of the reflected light irradiated from the light emitting element in the optical sensor PS, is The tone arm 1 is connected to the turntable T by using a tone arm 1 that has a surface that has fewer reflective surfaces than when there are no sound grooves, such as on the outer periphery of a record or between tracks. If records of various sizes are placed on the turntable T, the signal level of the output signal obtained from the optical sensor PS when the turntable T is rotated from the outside toward the center of the turntable T is ,
When the signal level is higher than a certain signal level in the vicinity of the area expected to be occupied by the outer circumference of the record placed on the turntable T, or when the record placed on the turntable T When the tone arm 1 exhibits an attenuation state equal to or higher than a predetermined signal level while moving toward the inside of the turntable near the area expected to be occupied by the outer circumference of the turntable, a record of the corresponding size is detected. D is determined to be placed on the turntable T, and the tone arm 1 is guided so that the playback needle is positioned at the standard lead-in position for the record of the corresponding size, and the performance is started. This is what I did.

Therefore, when the surface of the turntable T to be used in the automatic record player of the present invention is irradiated with light from the light emitting element in the optical sensor PS, the amount of reflected light given to the light receiving element in the optical sensor PS is However, when the outer periphery of a black record is irradiated with light from the light emitting element in the optical sensor PS onto a surface where there is no sound groove, such as between tracks, the amount of reflected light given to the light receiving element in the optical sensor is greater than the amount of reflected light given to the light receiving element in the optical sensor. A material that exhibits a surface condition that is similar to that of a small amount of material is used.
As a turntable that satisfies the above conditions,
For example, a matte black rubber sheet provided on the surface may be used.

Figure 5a shows a state in which a record D is placed on a turntable T, which has been designed to reduce the amount of light reflected from the surface by, for example, providing a matte black rubber sheet on the front surface. Figure 5b is a diagram showing the detection power of the optical sensor PS when the record D in Figure 5a has a high reflectance on its surface.
Figure c is a diagram showing the detection power of the optical sensor PS when the record D in Figure 5a is a black record.

In FIGS. 5b and 5c, the detection power of the optical sensor PS corresponding to the exposed surface of the turntable T is the lowest, and the detection force of the optical sensor PS corresponding to the exposed surface of the turntable T is lowest.
The change in the detection force of the optical sensor PS that appears at the edge of the record D appears large as shown in Figure 5b in the case of record D, which has a high surface reflectance.
In the case of a black record, it appears only small as shown in FIG. 5c.

Therefore, in the case of a record with a large surface reflectance, edges are detected by comparing the amount of change in the signal level that appears during the detection force of the optical sensor PS with an appropriate threshold voltage Vs. However, in the case of a black record, the amount of change in the signal at the edge portion does not reach the threshold voltage Vs as shown in Figure 5c, so in the case of a black record, light sensor
The edge of the record cannot be detected satisfactorily depending on the amount of change in the signal level that appears during the detection power of the PS.

Therefore, in the automatic record player of the present invention, there are various sizes of records (30cm disc, 25cm disc, 17cm disc) that are to be placed on the turntable T and are to be played. The sizes of records of various sizes are standardized, and when a record of any size is placed on the turntable T, the outer circumference of the record placed on it is occupies the area that the outer circumferential portion of a standard record having the size to which the record belongs would be occupied when placed on the turntable T;
Also, focusing on the fact that the area is constant for each record of each size, the optical sensor PS
Whether the detection power from
In the illustrated case}, or when the tone arm 1 is moving inward of the turntable T near the area Z, the detection force from the optical sensor PS exceeds a predetermined signal level. Whether or not the attenuation state is shown {in the case shown in Figure 5c...Regarding Figure 4, when the detection point position of the optical sensor PS moves from the non-recorded area on the outer periphery of the record to the subsequent recorded area (groove area) Due to the reasons explained, the detection power from the optical sensor PS decreases.
The system determines what size record is placed on the turntable T, and then lowers the playback needle to the standard lead-in position of the record placed on the turntable T. The tone arm 1 was made to be guided by.

The area occupied by the outer circumferential portion of the records of various sizes on the turntable T can be specified by the address signal of the playback needle position indicated by the output signal of the arm angle encoder AE mentioned above. The tone arm 1 can be moved from the outside of the turntable T to the inside of the turntable T by storing the address areas of the respective areas on the turntable T occupied by the outer peripheral portion of the tonearm 1 in the storage device in the control device CD. When the turntable T is rotated, the presence or absence of a record on the turntable T and the size of the record can be easily determined from the change in the detection force of the optical sensor PS that occurs within the memorized address area. be.

Now, the detection power in the form of an analog signal from the optical sensor PS is given to the AD converter ADC from the changeover switch SW via the line 25, and this AD converter
After being converted into a digital signal in the ADC, it is applied to the control device CD via the signal path 15.

The aforementioned changeover switch SW controls various signals from the stylus force adjustment signal generation circuit SP, the stylus position correction signal generation circuit SPS, the optical sensor PS, etc. by the switching control signal given from the control device CD via the signal path 14. As described above, the operation of switching the output signal and applying it to the AD converter ADC is performed.

Further, the motor control circuit MC supplies the turntable motor TM through a line 24 with the required driving power generated in response to a control signal applied via a signal path 22 from the control device CD. Also,
Information regarding the rotation angle of the turntable T is obtained from the motor control circuit MC, and this
Information regarding the rotation angle of the turntable T is given to the control device CD via the signal path 21 as information for correcting the radial address of the record, which changes due to eccentricity.

20 is a signal path for transmitting the output signal of the arm angle encoder AE mentioned above to the control device CD;
Further, 18 and 19 are a signal path 18 from the control device CD to the arm control circuit AC, and an information signal path 19 from the arm control circuit AC to the control device CD, and 16 is a key matrix.
The signal path 17 between KM and control device CD is the signal path for information from control device CD to display device DP.

Additionally, the muting switch MS is used to prevent the noise generated when the playback needle S comes into contact with the record surface due to the downward movement of the tone arm 1 from being generated in the playback sound. It is controlled by control signals transmitted via line 23 from the control device CD.

The automatic record player, which consists of each of the components described so far, performs automatic record playback, reserved playback, etc. in response to various operation modes given from a song selection designation operating device that includes a key matrix KM. Automatic performance of successive pieces of music corresponding to a plurality of pieces of music can be performed satisfactorily by the organically related operations of the respective constituent parts.

That is, in the automatic record player having the above configuration, the detection force by the optical sensor PS, whose positional relationship with the specific point of the tone arm 1 is maintained unchanged even when the head shell 6 is replaced, and the playback force of the cartridge 7. and an output signal from an arm angle encoder for generating an address signal indicating an address corresponding to the position of the tip of the needle 7 on the record radius (position on the radius of the turntable T).
Stored in the storage device (RAM) in the control device CD,
Since it is possible to read out the stored values of both of the signals mentioned above and perform comparison calculations, the position of the edge of the outer circumference of the record, the position of each inter-track band, etc. can be determined as an address on the radius of the turntable T prior to automatic playback. This allows you to accurately memorize it, and perform accurate lead-in operations for records of various sizes.
During the automatic performance operation for successive songs on a record, the tip of the playback needle S can be caused to be correctly brought down to the unrecorded portion immediately before the desired song.

Further, the address corresponding to the position on the radius of the turntable T of the detection point position P _sa by the optical sensor PS whose positional relationship with the specific point of the tone arm 1 is fixed is the address of the head shell 6. Tip position of regenerated needle S of cartridge due to replacement etc.
Arm angle encoder independent of changes in S _a
Taking advantage of the fact that there is always a correct correspondence with the address signal output from the AE, the address signal corresponding to the accurate address on the radius of the turntable T at the tip position of the playback needle S is output from the arm angle encoder AE. The cartridge can be easily obtained by subtracting the output address signal from the signal obtained by AD converting the needle position correction signal generated by the needle position correction signal generation circuit SPS by the AD converter ADC. Even if the tip position of the playback needle S of the cartridge changes due to replacement, etc., the address signal that corresponds to the correct address in the radial direction of the turntable T of the tip position S _a of the playback needle S will be sent during automatic record playback. It can be used to execute various operations.

In addition, since the address of the edge of a record can be clearly known, the address value and the standard address value of the edge for each record size can be used to determine the record size even if the record size is different. If the determination is made correctly, the playback needle S can be automatically guided to the introduction groove of the record.

Furthermore, address errors caused by errors in the mounting position of the tone arm can be prevented from becoming inappropriate in the introduction control by correcting the addresses for each record size.

Furthermore, even if the record is eccentric, the signal corresponding to the rotation angle of the turntable T is obtained from the motor control circuit MC and stored, and the height of the tone arm and the speed of descent in the vertical direction, etc. By using the method, the relationship between the rotation angle of the turntable before descending and the rotation angle of the turntable that should be at the time of contact is obtained.By calculating the time of contact from the current rotation angle, the regeneration hand S can be set. It is possible to always precisely place the tape on the inter-track band or on the non-recorded portion of the outer circumference of the record.

In addition, if you save the song numbers stored by reservation without deleting them when playing, even if the record player stops playing after all the songs corresponding to the stored song numbers are played, you can try again. If you request the start of the playback by operating the key matrix,
Automatic performance is repeatedly performed by repeatedly automatically playing songs whose numbers have been stored according to the reservation described above in the reserved order, or by generating a performance start signal at the end of the performance. Alternatively, the performance start signal of another automatic record player may be controlled by the performance start signal generated at the end of the performance.

The above-mentioned mutating switch MS is set to be turned off before the playback needle S lands on the record surface, and the mutating switch MS is set to be turned off before the playback needle S lands on the record surface. The on/off control is performed so that the on state is turned on after the tone arm changes or after an address change, but in order to perform the on operation in the above-mentioned on/off control, the vertical descent speed signal of the tone arm is used. is detected, and using a comparator that can generate an output signal when the speed proportional signal voltage falls below a predetermined voltage value, the time measuring means is started based on the output, and the time is measured. It is also possible that the muting switch MS is turned on by the output of the measuring means.

In addition, the detection power from the optical sensor PS mentioned above is
It is not only a matter of detecting the peak value from the detection force using a predetermined threshold value, but also the sharpness of the peak, the height of the peak, and the difference in height from the base value. Alternatively, the reliability of detecting inter-song bands can be increased by detecting a ratio or the like.

If the needle position correction signal generation circuit SPS has a configuration using a variable resistor as described above,
The address of the tip position of the regenerated needle S can be minutely changed by adjusting the variable resistor, so even if the tip position of the regenerated needle S changes due to replacement of the head shell, the tip of the regenerated needle can be adjusted by adjusting the variable resistor. It is extremely easy to ensure that the tone arm is correctly lowered into the band between songs, and it is also very easy to adjust the mounting position of the tone arm, which is a problem when automating record size detection and lead-in. Inconsistencies in lead-in addresses in records of various sizes caused by variations can also be easily corrected by adjusting the variable resistor.

Next, the block diagram shown in Fig. 1 and Fig. 6
The operation of the automatic record player of the present invention will be explained with reference to the flowcharts shown in FIGS.

After the power switch is turned on in step (0) of FIG. 6 and the device is put into an operable state, the operator inputs information by operating the keys of the key matrix KM. In step (10), the control device CD determines the key operation input given from the key matrix KM via the signal path 16, and if the key operation input is, for example, a reservation for a song number, the control device CD In step (20), the track numbers are sequentially stored in the storage device (RAM), and information regarding the track numbers is sent to the display device DP via the signal path 17.
to cause the display device DP to display the reserved song numbers in order.

In addition, if the key operation input is, for example, a reject, the control device CD goes to step (30).
The necessary information is exchanged with the arm control circuit AC via the signal paths 18 and 19 to return the tone arm to the armrest, and at the same time, the reserved content of the song number stored in the storage device is erased.

Further, if the key operation input is PLAY, the control device CD transmits the arm control circuit AC via the signal paths 18 and 19 in step (40).
The tone arm is raised from the armrest after transmitting and receiving the necessary information between the tone arm and the tone arm.

The arm control circuit AC described above drives two motors: a horizontal drive motor HM for rotating the tone arm 1 in the horizontal direction, and a vertical drive motor VM for rotating the tone arm 1 in the vertical direction. Information about the motor drive circuit and the state of the tone arm 1, that is, whether the tone arm 1 has stopped and reached the stopper position, and whether the tonearm 1 has reached the stopper position by rotating in the horizontal direction. The controller is equipped with a detection means for detecting information such as whether the playback needle S is in contact with the record surface or not, based on the state of increase in the drive current for the two motors. According to the control signal given from CD to the arm control circuit AC via the signal line 18,
In arm control circuit AC, horizontal drive motor HM and vertical drive motor from it's motor drive circuit
A necessary driving power is applied to the VM to raise or lower the tone arm 1, or to rotate it horizontally to the left or right, or to make it stand still. The detection result of the state of the tone arm 1 detected by the tone arm 1 is provided to the control device CD via the signal path 19. On the other hand, the control device CD controls the arm control circuit AC to start, continue, and stop operations such as raising, lowering, and rotating the tone arm in the left and right directions based on information given via the signal path. Give control signal. Thereby, the tone arm 1 can be freely moved vertically and horizontally in a required manner depending on each mode such as play mode, reject mode, reservation mode, etc. Note that the magnitude of the stylus pressure can be adjusted by varying the magnitude of the drive current to the vertical drive motor VM.

Following the play in step (40), in step (50), the size of the record placed on the turntable T is detected (the diameter of the record is 30 cm, 25 cm, etc.).
cm or 17 cm), and if a detection result indicating that there is no record on the turntable T is obtained, the process returns to step (30), and a record of the size with the detection result is obtained. If there is a reservation, the program proceeds to step (60), and in step (60) it is checked whether or not there is a reserved song selection.If there is a reservation, the band between songs is detected in step (70), ), if it is determined that there is no reservation, the playback needle S is positioned at the unrecorded portion of the outer circumference of the record of the record size obtained in step (50). Guide the tone arm 1 as desired.

Specifically, the detection of the record size in step (50) described above is carried out in steps (51) to 1 as shown in the flowchart of FIG. 7, for example.
(56). That is, in step (51), the tone arm 1 is rotated in the vertical direction by the vertical drive motor VM, and the tone arm 1 is raised until it is stopped by the upper limit stopper, and in that state, it is turned horizontally. Drive motor HM
to rotate the tone arm 1 horizontally to the left, and in step (52), the control device CD reads the address signal sent from the arm angle encoder AE via the signal path 20, In step 53), the control device CD determines whether the address indicated by the read address signal is at the innermost limit (leftmost position) in the movable range of the tone arm 1, and
If the judgment result in the step (53) is YES, it is assumed that there is no record on the turntable T, and the process proceeds to step (30) where a reject operation is performed, and the process proceeds to the step (53). If the judgment result in step (54) is yes, the detection power from the photosensor PS at the address obtained in the previous step (52) is applied to the AD converter ADC via the switch SW.
The digital signal obtained from the AD converter ADC is transferred to signal path 1.
5, it is stored in the storage device within the control device CD.

In step (55), a detection force equal to or higher than a predetermined signal level is obtained from the optical sensor PS in the address area of the outer periphery of records of various sizes prestored in the storage device in the control device CD. or when attenuation exceeding a predetermined signal level is obtained, it is determined that the optical sensor PS has passed the edge part of the record, and the address value read earlier in step (52) is determined in step (56). is applied to an address range predetermined for each record size to determine the record size.

Note that the time required for the loop of steps (52) to (55) described above is shorter than the time interval between successive address signals output by the arm angle encoder AE in accordance with the rotation of the tone arm 1. By adjusting the moving speed of the tone arm 1 in this way, it is possible to prevent a decrease in the positional accuracy of record edge detection.

As described above, after determining the record size in step (50), it is checked in step (60) whether there is a reservation, that is, a song selection request, and if there is a reservation, the process proceeds to step (70). (70) uses the same specific steps (51) to (55) in step (50) as described above, but in the case of step (70), the memorized past values are By sequentially storing the address values corresponding to the peaks in the storage device in the control device CD, the address values of successive inter-track bands in the record are sequentially stored in the storage device in the control device CD, and at the same time, Signal path 2
Information on the rotation angle of the turntable T given from the motor control circuit MC to the control device CD via the motor control circuit MC is also stored in association with the address of the peak value described above.

Next, in step (80), the reserved content of the song number is checked in the order of reservation, and the unrecorded area (the unrecorded part on the outer periphery of the record, or The address value corresponding to the band (interval band) is corrected using the signal obtained by AD converting the signal generated by the needle position correction signal generation circuit SPS by the AD converter ADC, and then by the arm control circuit AC. vertical drive motor
While supplying driving power to VM and horizontal drive motor HM and keeping tone arm 1 in the raised state, the address value after the above correction and the address value indicated by the address signal from arm angle encoder AE are The tone arm 1 is rotated to the left in the horizontal direction until they match, and when the tone arm 1 reaches the above position, the rotation of the tone arm 1 is stopped, and the tone arm 1 is rotated by driving the vertical drive motor VM. descend. And this step (80)
Now, continuing with the information on the rotation angle of the turntable T previously memorized in step (70), the point at which the playback needle S touches the record surface is approximately the same as the rotation angle indicated by the rotation angle information. In order to match, a necessary waiting time calculated from the start time of descent is set depending on the time required for the playback needle S to fall and the rotation period of the turntable T, so that even if the record is eccentric, playback will be possible. To enable a needle S to always come into contact with a predetermined record surface. Furthermore, the mutating switch MS is turned off before the playback needle S comes into contact with the record surface, and the mutating switch MS is turned on after the playback needle S comes into contact with the record surface.

In step (90), after the playback needle S comes into contact with the record surface, the vertical drive motor VM is still supplied with a drive current in the direction of lowering the tone arm 1;
Taking advantage of the fact that the magnitude of the drive current for VM increases rapidly after the playback needle S comes into contact with the record surface, the magnitude of the drive current for the vertical drive motor VM becomes larger than a predetermined current value. At the same time, a signal is generated and this signal is passed through the signal path 19.
to the control device CD, which in turn provides a control signal to the arm control circuit AC via signal path 18 to control the vertical drive motor.
Decrease the magnitude of the drive current supplied to the VM.

When a predetermined constant current is applied to the vertical drive motor VR, the playback needle S can be brought into contact with the record surface with a predetermined needle pressure, so that the playback needle S can produce the sound of the record. While tracing the groove, the variable resistor that constitutes the stylus pressure adjustment signal generation circuit SP is set so that the playback stylus S is in contact with the record surface at a predetermined stylus pressure. The voltage obtained by adjusting the slider of the device is applied to the vertical drive motor VM via the amplifier AMP, and the playback needle S is brought into contact with the record surface with a predetermined needle pressure.
The output from the stylus force adjustment signal generation circuit SP is given to the AD converter ADC via the switch SW, and the digital signal generated by this AD converter ADC is sent to the control device CD via the signal path 15. The signal is sent to the decoder, where it is decoded, and then sent to the display device DP via the signal path 17, where the stylus pressure is displayed on the display device DP. This display device DP also displays the number of the currently playing song, the number of the next song scheduled to be played, and the number of reserved songs remaining.

In order to know that the tone arm 1 is nearing the end of the song currently being played and has reached the inter-song band between the next song, the output signal of the arm angle encoder AE is obtained from the signal path 20 and Comparing the inter-song band position memorized at the time of music selection for reservation and the corresponding address value, if both address values match or the former address already exceeds the latter, the arm is sent via the signal path 18. A control signal is given to the control circuit AC to cause the tone arm 1 to be raised. If the result of the above comparison is that the two address values do not match, the process returns to the stylus pressure display operation described above and the address comparison is repeated. Similar to step (70), the comparison at this time is performed when the rotation angle of the turntable T also matches the stored value to prevent errors due to eccentricity of the record.

In step (100), after raising the tone arm 1, if there are any remaining songs in the reserved number of songs, return to step (80) and perform the operations from step (80) described above, and if there are remaining songs in the reserved number of songs. If so, go to step (30) and perform a reject operation.

In addition, in the above operation, the number of the song memorized by reservation is saved without being deleted at the time of performance, and the performance of the song corresponding to all the stored song numbers is completed. Even if the record player stops, you can use the key matrix KM to start playing again.
If a request is made by the operation, the songs with the song numbers stored by the reservation mentioned above will be automatically played repeatedly in the order specified, or a play start signal will be generated after the performance ends. In this way, the automatic performance can be repeatedly performed, or the performance start signal of another automatic record player can be controlled by the performance start signal generated at the end of the performance.

As is clear from the above explanation, in the automatic record player of the present invention, the optical sensor PS
Of the reflected light emitted from the light emitting element to the reflective surface in , the amount of light that reaches the light receiving element in the optical sensor PS is determined by the fact that the reflective surface is a surface where there are no sound grooves, such as the outer periphery or between tracks of a record. The output obtained from the optical sensor PS when the tone arm 1 is rotated from the outside of the turntable T toward the center of the turntable T using a turntable T having a surface that is smaller than that in the conventional case. If the signal level of the signal were to be placed on the turntable T, and records of various sizes were placed on the turntable T, the signal level would be around the area expected to be occupied by the outer circumferential portion of the record placed on the turntable T. When indicating a signal level state higher than a predetermined signal level, or when indicating an attenuation state higher than a predetermined signal level when the tone arm 1 moves toward the inside of the turntable T near the above-mentioned area. , determines that a record of the corresponding size is placed on the turntable T, guides the tone arm 1 so that the playback needle is positioned at the standard lead-in position for the record of the corresponding size, and starts playing. In the automatic record player of the present invention, even if the record to be played is a black record, or a record with a highly reflective surface such as a transparent or colored record, The tone arm 1 is guided so that the edge of the record is always well detected, the size of the record is accurately determined, and the playback needle is always automatically lowered to the correct lead-in position during automatic play. Therefore, according to the present invention, the drawbacks of the previously proposed automatic record players can be satisfactorily solved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the configuration of an automatic record player that automatically determines record size according to the present invention, FIG. 2 is a perspective view of an arm angle encoder, and FIG. 3 is a partially front cross-sectional view showing an optical sensor. , 4th
Figure a is an explanatory diagram of reflected light, Figure 4b, and Figures 5b and c are waveform diagrams of the detection force of the optical sensor, Figure 5a is a longitudinal sectional front view of a record on a turntable, 6 and 7 are flowcharts. KM...key matrix, CD...control device,
DP...Display device, AC...Arm control circuit, AE...Arm angle encoder, VM...Vertical drive motor, HM...Horizontal drive motor, MC...
…Motor control circuit, MS…mutating switch, PS…light sensor, SPS…needle position correction signal generation circuit, SP…stylus force adjustment signal generation circuit, SW…changeover switch, ADC…AD conversion instrument, S... playback needle, D... record, T... turntable, TM... turntable motor,
DESCRIPTION OF SYMBOLS 1... Tone arm, 2... Axis, 3... Code plate, 4... Light source row, 5... Photoelectric conversion element row, 6...
... head shell, 7 ... cartridge, 8 ... connection section, 10 ... case, 11 ... light shielding plate (partition),
12... Light source, 13... Light receiving element.

Claims (1)

[Claims] 1. A horizontal drive motor for horizontally rotating the tone arm, an address signal generator for generating an address signal corresponding to the horizontal rotation angle of the tone arm, and a horizontal drive motor for rotating the tone arm in the horizontal direction. Sometimes, the playback stylus attached to the tone arm is located at a position that traces a movement trajectory that roughly matches the arc-shaped movement path drawn by the tip of the playback stylus, and is located on the inner circumference side of the record relative to the cartridge installation position. An optical sensor is attached to the tone arm and has a light emitting element and a light receiving element to detect the state of light reflection on the turntable surface or record surface, and an address corresponding to the lead-in position for each record size. It stores the signal and compares the address signal corresponding to the lead-in position of the corresponding record size with the address signal obtained from the address signal generator described above to determine the lead-in position of the tone arm for each record size. Among the reflected light irradiated from the light-emitting element to the reflective surface in the optical sensor, the amount of light reaching the light-receiving element in the optical sensor is determined by the amount of light that reaches the light-receiving element in the optical sensor when the reflective surface is the outer periphery of the record. The turntable is equipped with a turntable having a surface where there is no sound groove, such as a part or a part between songs, and the tone arm is inserted into the center of the turntable from the outside of the turntable. If records of various sizes are placed on the turntable, the signal level of the output signal obtained from the optical sensor when rotated in the direction is When the signal level is higher than a certain signal level in the vicinity of the area expected to be occupied by the outer circumference of a record, or in the vicinity of the area expected to be occupied by the outer circumference of a record placed on the turntable. , when the tone arm is moving toward the inside of the turntable and exhibits an attenuation state that exceeds a predetermined signal level, it is determined that a record of the corresponding size is placed on the turntable. The automatic record player automatically determines the record size, and guides the tone arm so that the playback needle is positioned at the standard lead-in position for the record of the corresponding size, and starts playing.