Record

A record (12) comprising a convex protrusion (12a) at its center, one or more protrusions (12b) extending perpendicularly from the plane of the record at its circumferential edge, and a recording area between the center and the circumferential edge. The protrusions engage similar indentations (3b, 3e) formed in a turntable to facilitate centering and holding the record for playing and to prevent rotational slippage.

BACKGROUND OF THE INVENTION 
The present invention relates to a record applied to a sound reproducing 
apparatus for an audio signal such as voice, which initiates its 
reproducing operation only in response to the insertion of the record. 
Such a sound reproducing apparatus is known, in which a record is pressed 
against the central portion of a turntable after the record has been 
inserted and a tone arm is moved to its reproducing position to perform 
the reproducing operation. Upon the actuation of a release lever the tone 
arm and the record are lifted so that the record can be taken out of the 
apparatus. 
Conventionally, a flat disc-like record having a center hole has been used 
as a record applicable to such a reproducing apparatus. However, in order 
to freely use this reproducing apparatus without any trouble in any 
orientation of the apparatus, whether horizontal or vertical, it is 
necessary to provide a mechanism in the reproducing apparatus for 
preventing rotational slip of the record. Such rotational slip prevention 
mechanisms are complicated. In a reproducing apparatus of the type in 
which a record is mounted on a turntable, there is a further problem that 
slip may easily occur between the record and the turntable because very 
thin and very light records are often used. Further, it is necessary to 
insert the center hole of a record onto the center shaft of a turntable 
with a moderately tight fit in order to determine the center position of 
the record with respect to the turntable. There then arises a problem in 
the conventional reproducing apparatus that the mechanism for center hole 
insertion of a record onto the turntable is complicated. 
SUMMARY OF THE INVENTION 
An object of the present invention is therefore to provide a record which 
can remarkably simplify the mechanism for rotational slip of a record in a 
reproducing apparatus as well as simplify the mechanism for center 
positioning of the record on a turntable. 
The invention is a record having a central convex protrusion and additional 
protrusions on the circumferential edge to engage corresponding 
indentations in a turntable, thereby simplifying the sound playing 
apparatus needed for centering and rotating the record.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, an embodiment of the record according to the 
present invention will be described together with an example of the 
reproducing apparatus. 
In FIGS. 1 to 3, an upright shaft 2 is provided substantially at the 
central portion on the upper surface of a base 1 and a boss portion 3a of 
a turntable 3 is rotatably inserted onto the shaft 2. The upper end 
portion of a center hole of the turntable 3 which is to be inserted onto 
the shaft 2 is chamfered to form a conical surface 3b. A pin 3c is formed 
on the lower surface of the turntable 3 and a fly-wheel 4 is fixedly 
inserted onto the pin 3c. The fly-wheel 4 and the turntable 3 constitute a 
pulley 5. An electric motor 6 with a pulley 6a is mounted on the base 1 at 
one of its corners. A reduction idler pulley 7 is attached to the base 1 
between the motor 6 and the turntable 3. The motor pulley 6a and the idler 
pulley 7 are coupled to each other by a belt 8, while the idler pulley 7 
and the pulley 5 are coupled to each other by another belt 9. Thus, the 
rotational force of the motor 6 is transmitted to the turntable 3 through 
the pulley 6a, the belt 8, the idler pulley 7, and the belt 9 so as to 
rotate the turntable at a predetermined speed. 
A shaft bearing section 1a is formed at the rear end (upper end in FIG. 1) 
of the base so as to support a shaft 10a of a record press 10 such that 
the record press 10 can pivot about the shaft 10a in a plane perpendicular 
to the upper surface of the base 1. A projection 1b extending from the 
base 1 elastically contacts the shaft 10a of the record press 10 to 
prevent the record press from coming off. A free end section 10b of the 
record press 10 is placed above the shaft 2 which is the axis of 
revolution of the turntable 3. An arm 10c extends perpendicularly from a 
side surface of the record press 10. A ridge 10d is formed on the upper 
surface of the arm 10c in the longitudinal direction thereof as shown in 
FIG. 4. 
The forward end of the base 1 is overlayed with a record guide 11 such that 
a tunnel-like space is formed between the guide 11 and the upper surface 
of the turntable 3. A record 12 is inserted into this tunnel-like space in 
the direction of the turntable 3 with the recorded plane of the record 
made parallel to the turntable 3. As shown in FIGS. 6 and 7, the record 12 
has a convex protrusion 12a formed at its center on both its upper and 
lower surfaces. Protrusions 12b are also formed at equal distances along 
the circumferential edge of both its upper and lower surfaces. There may 
be any number of protrusions 12b including the case of one protrusion. The 
record also has a modulated groove section in the intermediate area 
between the convex protrusion 12a and the circumferential protrusions 12b. 
Inside the guide 11, guide walls 11a and 11a are formed for guiding the 
record when it is inserted. A guide groove 11b guides the convex 
protrusions 12a of the record 12. The convex protrusion 12a of the record 
12 falls into the conical hole 3b at the center of the turntable 3 when 
the record 12 is inserted through the tunnel-like space between the 
turntable 3 and the guide 11 and is moved to the correct position. 
An actuator lever 14 on the side of the record press 10 pivots about a 
shaft 13 extending from the base 1 in the plane parallel to the inserting 
direction of the record 12. A two-position selection spring 16 connected 
between one arm 14a of the actuator lever 14 and a shaft 15 formed on the 
base 1, so that it is made possible to cause the lever 14 to be 
selectively brought into either its clockwise rotated position or into its 
counterclockwise rotated position by causing the lever 14 to rotate beyond 
the dead point or change point of the spring 16, these positions being 
clockwise or counterclockwise as indicated in FIG. 1. An arm 14a projects 
from the side of the base 1 so that the user can swing the lever 14 by 
pulling the arm 14a or by actuating a not shown lever which engages the 
lever 14. A protrusion 14c is formed on the arm 14a of the lever 14. The 
other arm 14b of the lever 14 is positioned in the path of insertion of 
the record 12 when the lever 14 is brought into its counterclockwise 
rotated position as shown in FIG. 1 with a double-dotted line. On the 
other hand, when the arm 14b is put in its clockwise rotated position, it 
pushes an abutment knob 10e extending downwards from the lower surface of 
the record press 10 so that the record press 10 is forced by the abutment 
knob portion 10e to rotate counterclockwise as shown in FIG. 3 and as a 
result the free end section 10b of the record press 10 presses the convex 
protrusion 12a of the record 12 into the conical hole 3b of the turntable 
3. 
A tone arm supporting member 19 swings in a plane parallel with the 
turntable 3 about a shaft 18 attached to the base 1 in the vicinity of the 
actuator lever 14. An arm 19a extends outwards from the side of the tone 
arm supporting member 19, so that when the actuator lever 14 is rotated 
counterclockwise as shown in FIG. 1, the arm 19a is pushed by the 
protrusion 14c of the actuator lever 14 and therefore the tone arm 
supporting member 19 is caused to rotate counterclockwise. As shown in 
FIG. 4, the tone arm supporting member 19 supports a tone arm 21 rotatable 
about a horizontal shaft 20 in a plane perpendicular to the plane of the 
turntable 3. A pickup 22 is rigidly mounted on the tone arm 21. The tone 
arm 21 is forced by a not shown spring to swing counterclockwise as shown 
in FIG. 4 to press a stylus of the pickup 22 onto the recorded surface of 
the record 12 with a predetermined stylus pressure. The tone arm 21 is 
positioned above the arm 10c of the record press 10 so that when the 
record press 10 presses the record 12 to the turntable 3, the arm 10c of 
the record press 10 assumes its lowered position as indicated by a solid 
line in FIG. 4. The tone arm 21 is forcibly rotated to cause the stylus of 
the pickup 22 to be in contact with the modulated groove portion of the 
record 12. On the other hand, under the condition that the record 12 has 
been removed from the turntable 3, the arm 10c of the record press 10 is 
lifted to its upper position as indicated by a double-dotted line in FIG. 
4 and the tone arm 21 is pushed up by the ridge 10d on the upper surface 
of the arm 10c so as to cause the pickup 22 to lift off the record 12. An 
end plate 10f shown in FIG. 1 is attached at the end of the arm 10c so as 
to limit the counterclockwise swing of the tone arm 21. 
A sloping surface 10g is formed at the lower surface of the record press 10 
as shown in FIG. 3 so that when the actuator lever 14 is rotated 
counterclockwise as shown in FIG. 1, the upright edge of the other arm 14b 
of the actuator lever 14 pushes up the sloping surface 10g so as to cause 
the record press 10 to swing clockwise as shown in FIG. 3. This swing of 
the record press 10 causes the tone arm 21 to swing counterclockwise as 
shown in FIG. 4. Further, the counterclockwise swing shown in FIG. 1 of 
the actuator lever 14 causes the protrusion 14c to push the arm 19a of the 
tone arm supporting member 19 to swing the tone arm supporting member 19 
and the tone arm 21 counterclockwise. As shown in FIGS. 6 and 7, the 
turntable 3 is formed with at least one indentation 3e at its 
circumferential edge such that this indentation 3e may engage the 
protrusion 12b of the record 12. Further, the apparatus is arranged such 
that an electric power switch energizes the circuits of the motor 6, etc., 
when the actuator lever 14 is brought into its clockwise rotated position 
as indicated by a solid line in FIG. 1. 
The operation of the above-mentioned embodiment will now be described. The 
actuator lever 14 is in its counterclockwise rotated position as indicated 
by a double-dotted line in FIG. 1 under the condition that the record 12 
has not yet been mounted. Accordingly, the arm 14b of the lever 14 pushes 
the sloping surface 10g of the record press 10 so as to cause the record 
press to swing upwards with the result that the arm 10c of the record 
press 10 pushes up the tone arm 21 thereby causing the pickup 22 to come 
off from the record 12. Another result is that the protrusion 14c of the 
actuator lever 14 pushes the arm 19a of the tone arm supporting member 19 
to bring the tone arm 21 into its counterclockwise rotated position as 
indicated by a doubledotted line 21A in FIG. 1. 
Then the record 12 is inserted into the space between the record guide 11 
and the turntable 3. The record 12 is progressively inserted in the 
direction parallel to the plane of the turntable 3 while the outer 
periphery of the record 12 is guided by the guide walls 11a and 11a formed 
at the opposite sides of the guide 11. Also, the convex protrusion 12a of 
the record 12 is also guided by the guide groove 11b in the guide 11. As 
the record 12 moves, the arm 14b of the actuator lever 14 is pushed so 
that the lever 14 swings clockwise as shown in FIG. 1 and the protrusion 
14c comes away from the arm 19a of the tone arm supporting member 19. The 
swing of the lever 14 causes one of the support points of the two-position 
selection spring 16 to move beyond the change point so that the lever 14 
is brought into its clockwise rotated position by the force of the spring 
16 as indicated by a solid line in FIG. 1. In the rotational operation of 
the lever 14, the arm 14b of the lever 14 comes off the sloping surface 
10g of the record press 10 as shown in FIG. 3 to allow the record press 10 
to swing counterclockwise as shown in FIG. 3. At the same time, the arm 
14b of the lever 14 pushes the abutment knob 10e of the record press 10 to 
urge the record press 10 to swing counterclockwise as shown in FIG. 3. At 
this time, the convex protrusion 12a at the center of the record 12 is 
positioned at the center of the turntable 3 and the forward end section 
10b of the record press 10, forced to swing in the manner described above, 
pushes the convex protrusion to cause it to fall into the conical hole 3b 
of the turntable 3. Thereby the center positioning of the record 12 is 
accomplished and the record is put in its ready state to be rotated 
together with the turntable 3. 
The swing of the record press 10 by the above-mentioned force causes the 
arm 10c of the record press 10 to fall downward from the tone arm 21 as 
indicated by a solid line in FIG. 4. This allows the tone arm 21 to swing 
under the influence of the spring force to cause the stylus of the pickup 
22 to come down onto the modulated groove area of the record 12. Upon the 
closure of the power source switch and in response to the clockwise swing 
in FIG. 1 of the actuator lever 14, as described above, the motor 6 begins 
to rotate the turntable 3 and at the same time an audio amplifying circuit 
or the like is energized to reproduce an audio signal such as a voice 
recorded on the record 12. The record 12 is rotated together with the 
turntable 3 as formed thereon by the pressing force of the record press 10 
as well as by the engagement between the protrusion 12b provided at the 
circumferential edge of the record 12 and the indentation 3e formed at the 
circumferential edge of the turntable 3. In the playing or reproducing 
operation, the stylus of the pickup 22 moves along the modulated groove 
from the outermost track of the record 12 to the innermost one. Hence, the 
tone arm 21 and the tone arm supporting member 19 swing clockwise as 
indicated by a solid line shown in FIG. 1. 
When the playing operation is stopped and the record 12 is to be removed 
from the apparatus, the actuator lever 14 is swung counterclockwise in 
FIG. 1 either by direct manual operation or by the actuation of the 
release lever. The swing of the lever 14 causes its arm 14b to come off 
from the abutment knob 10e of the record press 10 and to strike the 
sloping surface 10g of the record press 10 so as to lift the record press 
10 and to thereby release the record 12 from the pressing force holding 
the same to the turntable 3. At the same time, the ridge 10d of the arm 
10c of the record press 10 pushes up the tone arm 21 to cause the pickup 
22 to rise off the record 12. Moreover, at this time the power source for 
the circuit of the motor, etc. has been turned off to de-energize the 
same. If the lever 14 is further swung, the arm 14b pushes the record 12 
towards the record insertion opening. The convex protrusion 12a of the 
pushed record 12 slides out of the conical hole 3b of the turntable 3. 
After passing over the change point of the two-position selection spring 
16, the swung lever 14 is brought into its counterclockwise rotated 
position as indicated by a double-dotted line as shown in FIG. 1. Thus, 
the protrusion 14c pushes the arm 19a of the tone arm supporting member 19 
to bring the tone arm 21 into its initial position as indicated by the 
double-dotted line 21A as shown in FIG. 1. In this state, the record 12 is 
partly exposed at the record insertion opening so that the record 12 can 
be taken out or can be reinserted to repeat the playing operation. 
According to the present invention, the record 12 is provided with a convex 
protrusion 12a at its center so that the center positioning of the record 
12 can be performed simply by causing the convex protrusion 12a to fall 
into a center hole formed by a chamfer 3b or other means on the turntable 
3, thereby remarkably simplifying the centering mechanism needed in the 
reproducing apparatus. Further, since the record can be easily inserted 
into and taken out of the reproducing apparatus while being guided with 
the convex protrusion 12a fitting along a guiding groove 11b, the guide 
mechanism can be markedly simplified. Moreover, since protrusions 12b are 
separately provided at the outer circumferential edge portion of the 
record, the rotational slip can be prevented by engaging protrusions 12b 
with corresponding indentations 3e formed on the upper circumferential 
edge of the turntable 3. The rotational slip preventing mechanism so 
provided is very simple. Further, the record can be pressed against the 
turntable only by pressing the convex protrusion 12a at the center of the 
record, whereby the mechanism for pressing the record can be simplified 
and frictional force can be reduced.