Device for driving minidisk player

A simple device for driving a minidisk player. This device carries out, using a common drive motor, both the disk loading/unloading operation and the pickup driving operation of the portable minidisk player. A power transmission gear is rotated by the rotational force of the common drive motor. The power transmission gear engages an idle gear which is moved by the turning motion of a link. This idle gear selectively engages either a disk loading gear or a pick up drive gear, thus to carry out the disk loading/unloading operation and the pickup driving operation. First and second locking units lock the idle gear to one of two predetermined positions so as to let the idle gear be rotated in opposed directions while engaging either the disk loading gear or the pickup drive gear. Each locking unit has a spring-biased turning member having a push projection. This push projection pushes a locking projection of the link to a stopper, thus to lock the link at a position, at which position the idle gear engages either the disk loading gear or the pickup drive gear.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates in general to a drive device for a portable 
minidisk player and, more particularly, to an improved structure in such a 
drive device for simplifying construction, reducing cost, and increasing 
compactness. 
2. Description of the Related Art 
Typical portable minidisk players generally use microcompact disks. 
Conventionally, such portable minidisk players play the microcompact disks 
in the order they are loaded by rotating the loaded disk and picking up 
information from the rotating disk by a pickup. To facilitate carrying the 
minidisk players, these players should be light, thin, small, simple, and 
compact. 
With reference to FIGS. 1, 2a and 2b, there is shown a disk loading part of 
a typical drive device for a portable minidisk player. In these figures, 
the front loading operation or the disk loading operation of the typical 
device is represented. 
In FIG. 1, the cartridge guide bracket for receiving a minidisk 1 is 
designated by the numeral 2. The guide bracket 2 is provided with a pair 
of projections 3 on each side. The pair of projections 3, spaced out at an 
interval, penetrate slant slits 5 of a power transmission rack 4 and in 
turn are inserted into slits 8 of a guide panel 7. The two guide panels 7 
are fixedly mounted on opposed sides of a deck 6. One guide panel 7 is 
shown in FIG. 1. The power transmission rack 4 engages and cooperates with 
a gear train 9. The drive spur gear of the gear train 9 engages a worm 
gear 11 mounted on the output shaft of a loading motor 10. 
When the cartridge guide bracket 2 is placed at the front disk inlet of the 
deck 6 and receives a new disk 1 therein as shown in FIG. 2a, the 
insertion of disk 1 is sensed by a limit switch (not shown). The limit 
switch, when sensing the disk insertion, outputs a disk sensing signal to 
start the loading motor 10. The rotational force of the loading motor 10 
is transmitted to the power transmission rack 4 through the worm gear 11 
and the gear train 9. The power transmission rack 4 linearly moves 
rightward in FIG. 2a, thereby starting the disk loading operation. 
When the power transmission rack 4 starts its rightward linear movement as 
shown in FIG. 2a, the projections 3 of the guide bracket 2 gradually 
linearly move in the horizontal sections of slits 8 of the guide panel 7. 
When the center of the disk 1 precisely coincides with the center of a 
turntable 12, the projections 3 of the guide bracket 2 reach the vertical 
sections of slits 8 of the panel 7 and, at the same time, descend along 
those vertical sections until seated on the bottoms of the vertical 
sections. As briefly described, the cartridge guide bracket 2, having the 
disk 1, moves back and down in the minidisk player under the guide of both 
slant slits 5 of the power transmission racks 4 and the slits 8 of the 
guide panels 7. The slits 5 and 8 cooperate with each other, and finish 
the disk loading operation. 
When unloading the disk 1, the loading motor 10 rotates in the opposite 
direction, and the power transmission racks 4 move leftward in FIG. 2b. 
The leftward linear movement of the power transmission racks 4 causes the 
projections 3 of the guide bracket 2 to be pushed up by the slant slits 5 
of the racks 4 and in turn to ascend along the vertical sections of the 
slits 8 of the guide panels 7. The projections 3 of the guide bracket 2, 
thereafter, move in the horizontal sections of the slits 8 of the guide 
panels 7, thus the cartridge guide bracket 2 reaches the front disk inlet 
of the player as shown in FIG. 2a. The disk unloading operation is thus 
finished. 
FIG. 3 is a sectional view of a pickup drive part of the typical minidisk 
player drive device. As shown in this drawing, the disk 1 is precisely 
seated on the turntable 12 as a result of the above disk loading 
operation. Turntable 12 is rotated by a spindle motor 13. When the disk 1 
is precisely seated on the motor-driven turntable 12, a pickup 16 starts 
the operation of picking up the information of the disk 1. This pickup 16 
is driven by a lead screw 15. The lead screw 15 is rotated by the 
rotational force of a pickup drive motor 14 that is placed at a side of 
the spindle motor 13. To transmit the rotational force of the pickup drive 
motor 14 to the lead screw 15, a plurality of gears are arranged between 
and engaged with the output shaft of the motor 14 and the lead screw 15. 
In this case, the pickup 16 in its initial position should be placed above 
the center of the disk 1. 
However, it has been noted that the typical device for driving the portable 
minidisk player has the following problems. 
The typical minidisk player drive device should have at least two motors, 
that is, the loading motor 10 and the pickup drive motor 14, for carrying 
out the disk loading/unloading operation and driving the pickup 16 
respectively. With the two motors, the cost of the minidisk player is 
increased. The expensive cost deteriorates the competitive power of the 
products. 
The above drive device uses the gear train 9 for linear reciprocation of 
the power transmission rack 4, so that the loading motor 10 should use a 
large capacity and large-sized motor. The gear train 9 also occupies 
considerable space in the drive device and, as a result, enlarges the size 
of the player. This directly runs counter to the recent trend of 
compactness of the portable minidisk players. 
SUMMARY OF THE INVENTION 
It is, therefore, an object of the present invention to provide a device 
for driving a minidisk player in which the aforementioned problems can be 
overcome and which carries out, using one drive motor, both the disk 
loading/unloading operation and the pickup driving operation of the 
portable minidisk player. 
In order to accomplish the above object, a device for driving a minidisk 
player in accordance with an embodiment of the present invention 
comprises: a drive motor mounted on a deck; a power transmission gear 
rotated by rotational force of the motor; friction means coming into 
surface contact with the power transmission gear; a link coming into 
surface contact with the friction means, the link being turned clockwise 
or counterclockwise depending on rotating direction of the power 
transmission gear; an idle gear rotatably mounted on the link and rotated 
by rotational force of the power transmission gear; a disk loading gear 
placed in turning range of the link, the loading gear gearing into the 
idle gear during a disk loading/unloading operation, thus to make a 
cartridge guide bracket reciprocating; a pickup drive gear placed in the 
turning range of the link, the pickup drive gear gearing into the idle 
gear during a pickup driving operation, thus to drive a pickup; and first 
and second locking units for locking the idle gear to one of predetermined 
two positions so as to let the idle gear be rotated in opposed directions 
while gearing into either the disk loading gear or the pickup drive gear.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the following description of an embodiment of this invention, those 
elements common to both the embodiment of this invention and the prior art 
embodiment of FIG. 1 will carry the same reference numerals. 
FIGS. 4a and 4b are plan views showing the construction and operation of a 
disk player drive device in accordance with a preferred embodiment of the 
present invention. FIG. 5a is a perspective view showing the relative 
position between a power transmission gear and a link of the drive device. 
FIG. 6 is a plan view showing an initial state of a pickup of the drive 
device of the present invention. FIGS. 7a and 7b are perspective views of 
first and second turning members of the drive device of the present 
invention respectively. 
As shown in FIGS. 4a and 4b, the disk player drive device of the present 
invention comprises a drive motor 17 fixedly mounted on a deck 6. This 
motor 17 is connected to a power transmission gear 18 and transmits its 
rotational force to the gear 18, thus to rotate the gear 18. Friction 
means comes into surface contact with the top surface of the power 
transmission gear 18. The above friction means also comes into surface 
contact with the bottom surface of a link 20. This link 20 is turned 
clockwise or counterclockwise depending on the rotating direction of the 
power transmission gear 18. An idle gear 19 is rotatably mounted on the 
link 20 and is rotated by the rotational force of the power transmission 
gear 18. The drive device also includes a loading gear 22 which is 
rotatably mounted on the deck 6 in the turning range of the link 20. The 
loading gear 22 selectively gears into the idle gear 19 during the disk 
loading/unloading operation, thus to make the cartridge guide bracket 
reciprocating. A pickup drive gear 25 is rotatably mounted on the deck 6 
in the turning range of the link 20. The pickup drive gear 25 selectively 
engages the idle gear 19 during the pickup driving operation, thus to 
drive the pickup 16a. So that the idle gear 19 rotates in opposed 
directions while smoothly engaging either the loading gear 22 or the 
pickup drive gear 25, the drive device further includes a pair of locking 
units. The pair of locking units lock the idle gear 19 into one of two 
predetermined positions. At each of the two positions, the idle gear 19 
engages either the loading gear 22 or the pickup drive gear 25. 
In the above player drive device, the power transmission gear 18 may be 
indirectly applied with the rotational force of the motor 17 through a 
drive gear 21, which gear 21 is fixed to the output shaft of the motor 17, 
as shown in FIGS. 4a and 4b. Alternatively, the power transmission gear 18 
may be directly applied with the rotational force of the motor 17. In this 
case, the power transmission gear 18 may be directly fixed to the output 
shaft of the motor 17. 
As shown in FIG. 5a, the friction means coming into surface contact with 
both the power transmission gear 18 and the link 20 is a wool disc 38 
interposed between the gear 18 and the link 20. This wool disc 38 used as 
the friction means is fixedly mounted on either the gear 18 or the link 20 
and rotates the link 20 in the rotating direction of the power 
transmission gear 18. 
The loading gear 22 for reciprocating the cartridge guide bracket engages 
either its driven gear or a first driven gear 24 which is in turn coupled 
to a first lead screw 23. In the same manner, the pickup drive gear 25 for 
driving the pickup 16a engages either its driven gear or a second driven 
gear 27 which is in turn coupled to a second lead screw 26. 
The first locking unit comprises a solenoid 33 mounted on the deck 6. A 
first locking projection 20a is integrally formed on a side of the link 
20, such that it is turned in opposed directions depending on the opposed 
directional turning motion of the link 20. The first locking unit also 
includes a first stopper 28 fixedly mounted on the deck 6. This first 
stopper 28 will be engaged with the first locking projection 20a of the 
link 20 when the idle gear 19 engages the loading gear 22 for carrying out 
the disk loading/unloading operation. A locking sensor (not shown) is 
provided to sense the engagement of the first locking projection 20a with 
the first stopper 28. The first locking unit further includes a first 
turning member 29 rotatably mounted on the deck 6. This first turning 
member 29 is turned clockwise about its hinged shaft 31 by the magnetic 
force of the solenoid 33 so as to be closer to the first stopper 28 when 
the locking sensor senses the engagement of the first locking projection 
20a with the first stopper 28. A first push projection 29a is integrally 
formed on an end of the first turning member 29. When the idle gear 19 
engages the loading gear 22 so as to carry out the loading operation as 
shown in FIG. 4a, the first locking projection 20a of the link 20 will be 
tightly sandwiched between the first stopper 28 and the first push 
projection 29a of the turning member 29, thus to reliably retain the idle 
gear 19 engaging the loading gear 22. 
In order to prevent a possible interference between the first turning 
member 29 and the first locking projection 20a during the turning motion 
of the link 20 for the engagement of the first locking projection 20a with 
the first stopper 28, the first turning member 29 is biased by first 
spring means or a first tension coil spring 32. When carrying out the disk 
loading/unloading operation, the above first turning member 29 should be 
turned clockwise about its hinged shaft 31 while overcoming the spring 
force of the coil spring 32 or tensioning this spring 32. This object is 
achieved by a metal piece 30 which is mounted on the other end of the 
first turning member 29 and attracted by the magnetic force of the 
solenoid 33. The structure of the first turning member 29 is shown in 
detail in FIG. 7a. 
The second locking unit comprises a second locking projection 20b. This 
second projection 20b is integrally formed on the other side of the link 
20, such that it is turned in opposed directions depending on the opposed 
directional turning motion of the link 20. The second locking unit also 
includes a second stopper 34 fixedly mounted on the deck 6. This second 
stopper 34 will be engaged with the second locking projection 20b of the 
link 20 when the idle gear 19 engages the pickup drive gear 25 for 
carrying out the pickup driving operation. The second locking unit further 
includes a second turning member 35. This second turning member 35 is 
turned clockwise about its hinged shaft 36 by the spring force of second 
spring means or of a second tension coil spring 37 so as to be closer to 
the second stopper 34 when the second locking projection 20b is engaged 
with the second stopper 34. 
A second push projection 35a is integrally formed on an end of the second 
turning member 35. When the idle gear 19 engages the pickup drive gear 25 
so as to carry out the pickup driving operation as shown in FIG. 4b, the 
second locking projection 20b of the link 20 will be tightly sandwiched 
between the second stopper 34 and the second push projection 35a of the 
second turning member 35, thus to reliably retain the idle gear 19 
engaging into the pickup drive gear 25. The second tension coil spring 37 
is coupled to the other end of the second turning member 35 and biases the 
member 35 so as to turn this member 35 clockwise. When the idle gear 19 
engages into and rotates the pickup drive gear 25 and moves the pickup 16a 
to its initial position, the pickup 16a pushes the other end 35b of the 
second turning member 35 so as to turn the second turning member 35 
counterclockwise while overcoming the spring force of the spring 37 or 
tensioning this spring 37. Because of the counterclockwise turning motion 
of the second turning member 35, the second push projection 35a of the 
member 35 releases the second locking projection 20b of the link 20 which 
has been locked to the second stopper 34. The structure of second turning 
member 35 is shown in detail in FIG. 7b. In the player drive device of 
this embodiment, the initial position of the pickup 16a is closer to the 
center of the turntable 12 by a predetermined distance .delta. in 
comparison with the conventional pickup initial position as shown in FIG. 
6. 
The operational effect of the above player drive device will be given 
hereinbelow. 
When the cartridge guide bracket has no disk therein, the positions of the 
elements of the drive device are shown in FIG. 4a. In this state, the 
solenoid 33 is turned off and generates no magnetic force, so that the 
first tension coil spring 32 pulls the first turning member 29. Hence, the 
first turning member 29 is retained in its idle position shown at the dash 
and dot in FIG. 4a. The pickup 16a pushes the other end 35b of the second 
turning member 35, so that the second turning member 35 is retained in its 
idle position while overcoming the spring force of the second tension coil 
spring 37. In this case, the link 20 is locked to no element of the 
device. 
When a disk 1 is inserted into the cartridge guide bracket, a limit switch 
(not shown) senses the insertion of the disk 1 and outputs a sensing 
signal, thus to start the motor 17. At this time, the motor 17 is rotated 
counterclockwise in the drawing and rotates the drive gear 21 in the same 
direction. The power transmission gear 18 gearing into the drive gear 21 
is thus rotated clockwise in the drawing. The clockwise rotational force 
of the power transmission gear 18 is transmitted to the link 20 through 
the wool disc 38 interposed therebetween, thus to rotate the link 20 
clockwise. Therefore, the idle gear 19 coupled to the link 20 engages the 
loading gear 22 and, at the same time, the first locking projection 20a of 
the link 20 engages the first stopper 28. 
The above engagement of the first locking projection 20a of the link 20 
with the first stopper 28 is sensed by the locking sensor. After sensing 
the engagement, the locking sensor turns on the solenoid 33. This solenoid 
33 thus generates the magnetic force which attracts the metal piece 30 of 
the first turning member 29. Hence, the first turning member 29 is turned 
clockwise about its hinged shaft 31 while overcoming the spring force of 
the first tension coil spring 32 as shown at the solid line of FIG. 4a. 
With the clockwise turning motion of the first turning member 29, the 
first push projection 29a of the turning member 29 pushes the first 
locking projection 20a to the first stopper 28, thus sandwiching the first 
locking projection 20a between the first push projection 29a and the first 
stopper 28 as shown in FIG. 4a. 
When the first locking projection 20a of the link 20 is sandwiched between 
the first push projection 29a and the first stopper 28, the rotational 
force of the power transmission gear 18 is reliably transmitted to this 
loading gear 22 through the idle gear 19, thus to rotated the loading gear 
22. The loading gear 22 thus rotates both the first driven gear 24 and the 
first lead screw 23, thereby seating the cartridge guide bracket coupled 
to the lead screw 23 on its loading place in the deck 6. The disk loading 
operation is thus finished. 
After the disk loading operation, the solenoid 33 is turned off and does 
not generate the magnetic force any more, so that the first turning member 
29 is pulled by the first tension coil spring 32 and turned 
counterclockwise about its shaft 31. The counterclockwise turning motion 
of the first turning member 29 frees the first locking protrusion 20a of 
the link 20 from the first push projection 29a of the member 29. 
Therefore, the link 20 is engaged with no element and applied with no 
outside force. 
After the outside force biasing the link 20 is removed, the motor 17 is 
rotated clockwise in the drawing and rotates the drive gear 21 in the same 
direction. The power transmission gear 18 is thus rotated counterclockwise 
in the drawing. The counterclockwise rotational force of the power 
transmission gear 18 is transmitted to the link 20 through the wool disc 
38, thus to rotate the link 20 counterclockwise. Therefore, the idle gear 
19 coupled to the link 20 engages the pickup drive gear 25 and, at the 
same time, the second locking projection 20b of the link 20 is engaged 
with the second stopper 34. 
When the link 20 is turned toward the pickup drive gear 25, there is no 
interference between the second turning member 35 and the second locking 
projection 20b since the second turning member 35 is pushed by the pickup 
16a placed in its initial position. That is, since the second turning 
member 35 is retained in its counterclockwise biased state while 
overcoming the spring force of the second tension coil spring 3, no 
interference is generated between the second push projection 35a of the 
second turning member 35 and the second locking projection 20b of the link 
20 during the counterclockwise turning motion of the link 20. 
As a result of gearing the idle gear 19 of the link 20 into the pick drive 
gear 25, the second driven gear 27 is rotated. The pickup 16a coupled to 
the lead screw 26 thus starts its linear movement in leftward direction as 
shown at the arrow of FIG. 4a. The leftward directional movement of the 
pickup 16a removes the outside force applied from the pickup 16a to the 
other end 35b of the second turning member 35, thus to let the second 
turning member 35 be turned clockwise by the restoring force of the second 
tension coil spring 37 as shown in FIG. 4b. With the clockwise turning 
motion of the second turning member 35, the second push projection 35a of 
the second turning member 35 pushes the second locking projection 20b to 
the second stopper 34, thus to make this second locking projection 20b 
sandwiched between it and the second stopper 34 as shown in FIG. 4b. 
When the second locking projection 20b of the link 20 is sandwiched between 
the second push projection 35a and the second stopper 34, the rotational 
force of the power transmission gear 18 is reliably transmitted to the 
pickup drive gear 25 through the idle gear 19, thus to rotated this pickup 
gear 25. The pickup drive gear 25 thus rotates both the second driven gear 
27 and the second lead screw 26 and in turn reciprocates the pickup 16a, 
which is coupled to the lead screw 26, across the loaded disk 1. 
The locking of the second locking projection 20b of the link 20 by 
sandwiching it between the second stopper 34 and the second push 
projection 35a of the second turning member 35 is for returning the pickup 
16a to its initial position. Otherwise stated, in order to return the 
pickup 16a to its initial position, the drive motor 17 should be rotated 
counterclockwise. When the link 20 is not locked during the above 
counterclockwise rotation of the drive motor 17, the idle gear 19 will be 
separated from the pickup drive gear 25 and this makes the returning of 
the pickup 16a to its initial position impossible. 
When the disk 1 needs ejecting from the disk player after picking up the 
information of the disk 1, the drive motor 17 is rotated counterclockwise 
in the drawing under the control of a microcomputer (not shown), thus to 
return the pickup 16a to its initial position as shown in FIGS. 4a and 6. 
At this time, the initial position of the pickup 16a is closer to the 
center of the turntable 12 by the predetermined distance .delta. in 
comparison with the conventional pickup initial position as shown in FIG. 
6. As a result of returning of the pickup 16a to its initial position, the 
other end 35b of the second turning member 35 is pushed leftward in the 
drawing by the pickup 16a while overcoming the spring force of the second 
tension coil spring 37. The biasing force applied from the second push 
projection 35a of the second member 35 to the second locking projection 
20b of the link 20 is removed. 
When unloading or ejecting the disk 1, the motor 17 is rotated 
counterclockwise in the drawing and rotates the drive gear 21 in the same 
direction. The power transmission gear 18 gearing into the drive gear 21 
is thus rotated clockwise in the drawing. The clockwise rotational force 
of the power transmission gear 18 is transmitted to the link 20 through 
the wool disc 38 interposed therebetween, thus rotating the link 20 
clockwise. Therefore, the idle gear 19 coupled to the link 20 engages the 
loading gear 22 and, at the same time, the first locking projection 20a of 
the link 20 is engaged with the first stopper 28. 
The above engagement of the first locking projection 20a of the link 20 
with the first stopper 28 is sensed by the locking sensor and turns on the 
solenoid 33. This solenoid 33 thus generates the magnetic force which 
attracts the metal piece 30 of the first turning member 29. Hence, the 
first turning member 29 is turned clockwise about its hinged shaft 31 
while overcoming the spring force of the first tension coil spring 32. 
With the clockwise turning motion of the first turning member 29, the 
first push projection 29a of the second turning member 29 pushes the first 
locking projection 20a to the first stopper 28, thus sandwiching the first 
locking projection 20a between the first push projection 29a and the first 
stopper 28 as shown in FIG. 4a. 
When the first locking projection 20a of the link 20 is sandwiched between 
the first push projection 29a and the first stopper 28, the drive motor 17 
is rotated in a direction reverse to that of the above disk loading 
operation. The disk unloading operation is thus finished. 
As described above, a device for driving a minidisk player in accordance 
with the present invention uses one drive motor commonly used for both the 
disk loading/unloading operation and the pickup driving operation, thus to 
reduce the cost. The player drive device does not need a gear train unlike 
the typical device, so that it does not need a large capacity and 
large-sized motor as the loading motor. With the simple structure of the 
player drive device having no gear train, the device occupies a small 
space, thus saving the space. This makes the minidisk player small-sized 
and achieves the recent trend of compactness of the disk player, 
particularly of the portable minidisk player. 
Also, with the described device, the initial position of the pickup may be 
closer to the center of the turntable, by a predetermined position, than a 
convention pickup initial position. 
Although the preferred embodiments of the present invention have been 
disclosed for illustrative purposes, those skilled in the art will 
appreciate that various modifications, additions and substitutions are 
possible, without departing from the scope and spirit of the invention as 
disclosed in the accompanying claims.