Tape cassette loading device for cassette tape recorder

A tape cassette loading device for a cassette tape recorder comprises a brushless motor capable of immediately starting to rotate in response to an external starting drive in a direction determined by such drive and also capable of immediately stopping in response to an external braking effort. A movement of a cassette holder is transmitted through a holder drive mechanism to the motor, thereby controlling the motor.

BACKGROUND OF THE INVENTION 
The invention relates to a tape cassette loading device for a cassette tape 
recorder. 
A slide-in mechanism of the Staar type is known as a device which loads a 
tape cassette into a cassette tape recorder. In this instance, a tape 
cassette is slid into the recorder from an opening formed in the front 
surface thereof. A pilot pin is then urged by the cassette inserted to 
operate a linkage, which causes a movable carriage carrying drive 
elements, such as a capstan or reel shafts, to be lifted into engagement 
with a capstan receiving aperture and tape hubs, respectively, formed in 
the cassette. However, the described arrangement is susceptible to 
oscillations since the capstan, reel shafts and their associated drive 
mechanisms are mounted on the moving carriage, disadvantageously causing a 
nonuniform rotation. To eliminate these drawbacks of the Staar type 
arrangement, there is proposed a tape cassette loading device which may be 
referred to as a fixed drive mechanism type in that the reel shafts, 
capstan and their drive mechanisms are mounted on a fixed substrate. In 
this device, when a tape cassette is inserted into a cassette receiving 
opening and receiving in a cassette holder, the latter moves further 
inward and then moves down to engage the capstan receiving aperture and 
tape hubs formed in the cassette with the reel shafts and the capstan 
mounted on the fixed substrate. This conventional arrangement requires a 
specific starting means associated with an electric motor which is 
utilized to move the cassette holder, and disadvantageously results in a 
complex construction and a reduced operating ease. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a tape cassette loading device 
for a cassette tape recorder of the fixed drive mechanism type in which a 
brushless motor capable of immediately starting to rotate in response to 
an external starting drive in a direction determined by such drive and 
capable of immediately stopping in response to an external braking effort 
is used in a holder drive mechanism which is adapted to carry a cassette 
holder, receiving and retaining a tape cassette, in a given location, the 
arrangement being such that an external starting drive or braking effort 
is applied to the motor through the holder drive mechanism to facilitate a 
loading and a removal of the tape cassette. 
In accordance with the invention, a brushless motor capable of immediately 
starting to rotate in response to an external starting drive or capable of 
immediately stopping in response to an external braking effort is 
connected to a cassette holder through a holder drive mechanism. 
Accordingly, when loading a tape cassette, the insertion of a tape 
cassette into the cassette holder and a slight manual movement of the 
cassette holder are all that is required to load the cassette in place. 
Specifically, the external starting drive is applied to the brushless 
motor through the holder drive mechanism, causing the motor to start its 
rotation. When the holder has been moved to a given cassette loading 
location as a result of rotation of the motor, the completion of movement 
of the cassette holder applies a braking effort to the brushless motor, 
which therefore ceases to rotate. When it is desired to remove the tape 
cassette from a recorder, an eject button may be operated to cause the 
cassette holder to move slightly. Thereupon, an external starting drive is 
applied to the brushless motor through the drive mechanism, thus enabling 
the motor to be set in motion. As a result of such rotation, the cassette 
holder is driven from its loading position to its cassette insertion 
position. The completion of the movement of the cassette holder applies a 
braking effort to the brushless motor, which therefore ceases to rotate. 
Thus, the tape cassette can be removed automatically.

DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring to FIG. 1, there is shown a tape cassette loading device 10 which 
is assembled into a cassette tape recorder 12. It will be seen that the 
cassette loading device 10 has a front panel in which an opening 14 is 
formed to permit the insertion of a tape cassette. As shown in FIG. 2, a 
tape cassette 16 may be inserted into the opening 14. An open-ended 
box-like cassette holder 15 is disposed rearwardly of the opening 14, or 
to the left thereof as viewed in FIG. 2, to receive and retain the 
cassette 16 as it is inserted into the opening 14. Toward its forward end, 
the bottom of the cassette holder 15 is formed with a plurality of spring 
blades 18 (see FIGS. 3 and 4) for resiliently holding the cassette 16 
inserted against unintended movement. The cassette loading device includes 
a housing 13 having a pair of opposite lateral sidewalls 13a, 13a' (see 
FIG. 3) in which guide slots 36, 36' are formed in an L-configuration 
having its horizontal limb which is contiguous with a downwardly depending 
limb which extends from the rear end of the former. A pair of engaging 
pins 32, 32' (see FIG. 4) are fixedly mounted on the outside of the 
sidewalls of the cassette holder 15 and engage the guide slots 36, 36' to 
guide the movement of the cassette holder 15. The cassette tape recorder 
includes a lower substrate 38 on which reel shafts 40, 41, pinch roller 46 
and capstan 48 are mounted for driving and controlling the running of a 
cassette tape. When the cassette holder 15 carrying the cassette 16 
therein moves down along the guide slots 36, 36', the reel shafts 40, 41 
and the capstan 48 engage the capstan receiving aperture and tape hubs 
formed in the cassette 16, thus permitting the running of the cassette 
tape to be controlled. 
In accordance with the invention, the cassette loading device 10 employs a 
brushless motor 20 which is shown rearwardly and upwardly, as viewed in 
FIG. 2. This motor can be controlled by a brushless motor control circuit 
as disclosed in Japanese Laid-Open Patent Application No. 28,623/1975, and 
is adapted to start rotating immediately in response to an external 
starting drive in a direction determined by such drive and to stop 
immediately in response to an external braking effort. As shown in detail 
in FIG. 4, the motor 20 is connected to the cassette holder 15 through a 
holder drive mechanism 22 which comprises a plurality of gears 23, 24, 25, 
28, 30; 23', 24', 25', 28', 30' and endless timing belts 26, 26'. 
Specifically, a pair of laterally spaced output gears 30, 30' are 
integrally mounted on the opposite end portions 20a, 20a' of the rotary 
shaft of the motor 20, and a pair of laterally spaced transmission gears 
28, 28' mesh with these gears 30, 30', respectively. The transmission 
gears 28, 28' are mounted on shafts 28a, 28a' on which a pair of 
laterally spaced gears 23, 23' are integrally mounted. These gears 23, 23' 
mesh with a rack formed on the inside of a pair of laterally spaced 
endless timing belts 26, 26', which also extend around pairs of laterally 
spaced gears 24, 24' and 25, 25', which also mesh with these belts. As 
shown in FIG. 5, these endless timing belts 26, 26' are formed with an 
engaging apertures 34 or 34', respectively, which is in turn engaged by 
the engaging pin 32, 32' fixedly mounted on the sidewalls of the cassette 
holder 15 and extending through the guide slots 36, 36', in a manner as 
indicated in FIG. 4. Consequently, as the brushless motor 20 is set in 
motion, the drive therefrom is transmitted through the gear pairs 30, 30'; 
28, 28'; 23, 23' to the endless timing belts 26, 26', the movement of 
which is transmitted to the cassette holder 15 through the engagement 
between the apertures 34, 34' and the pins 32, 32', thus causing the 
cassette holder 15 to move along the guide slots 36, 36'. In this manner, 
the cassette holder 15 is movable between a cassette insertion position 
illustrated in FIG. 2 and a cassette loaded position illustrated in FIG. 
6. As shown in FIGS. 2 and 3, the front panel of the cassette loading 
device 10 is provided with an eject button 52 which is used to remove a 
loaded cassette. As shown in FIG. 6, the eject button 52 is formed by one 
end of a lever 50 which is rockably mounted on a pin which is secured to a 
stationary port such as the housing, and a torsion spring 54 is disposed 
on the pivot pin and engages one arm of the lever to urge the lever 
counter-clockwise, as viewed in FIG. 6, about the pivot. At this time, the 
lever 50 stays at rest while its other end 58 abuts against the bottom of 
the housing 13. When the eject button 52 is depressed downward, the lever 
50 pivots clockwise against the resilience of the torsion spring 54, with 
the end 58 striking the bottom of the cassette holder 15 which is situated 
as shown in FIG. 6, thus driving it upward. 
In operation, when it is desired to insert the cassette 16, it is inserted 
into the cassette holder 15 through the opening 14, with a slight 
pressure, as indicated in FIG. 2. When inserted into the holder 15, the 
cassette 16 is gently held by the plurality of spring blades 18, and as 
the cassette 16 is pushed further inward to apply a driving force to the 
holder 15, the latter moves inward along the guide slots 36, 36'. Such 
movement of the holder 15 is transmitted through the pins 32, 32' to the 
timing belts 26, 26' of the holder drive mechanism 22, thus driving the 
belts 26, 26' in directions indicated by arrows w1, w1' shown in FIG. 4. 
Such movement of the belts 26, 26' is effective to rotate the gears 23, 
23' and 28, 28' counter-clockwise and to rotate, in turn, gears 30, 30' 
clockwise, thus applying a starting drive to the rotary shaft ends 20a, 
20a' of the motor 20. In response thereto, the motor 20 is immediately set 
in motion, whereby the transmission through the gears 30, 30'; 28, 28'; 
23, 23' of the drive from the rotating motor 20 continues to drive the 
belts 26, 26' in the directions of arrows w1, w1', causing the cassette 
holder 15 which carries the cassette 16 therein further inward along the 
guide slots 36, 36'. As mentioned previously, the rear portion of the 
guide slots 36, 36' is bent to extend downwardly in the manner of a letter 
L, and the belts 26, 26' are bent in a similar configuration. Hence, when 
the cassette holder 15 moves rearwardly from the insertion position shown 
in FIG. 2, it is then driven downward to reach the position shown in FIG. 
6 where the guide slots 36, 36' terminate, thus preventing a further 
downward movement of the holder 15. Consequently, a further movement of 
the belts 26, 26' is interrupted as is the rotation of the gear pairs 23, 
23'; 28, 28'; 30, 30'. Consequently, a braking effort is applied to the 
shaft ends 20a, 20a' of the motor 20 to stop its rotation. It will be 
appreciated from the foregoing description that when the cassette holder 
15 reaches the position shown in FIG. 6, the cassette 16 carried therein 
is located so that the tape hubs and the capstan receiving apertures 
formed therein are fitted over the reel shafts 40, 41 and the capstan 
shaft 48, respectively, which are disposed on the substrate 38, whereby 
the apparatus is ready to operate. 
FIG. 7 shows an electrical circuit which is used in the cassette tape 
recorder 12 shown in FIG. 1. It includes a power source E, a pair of 
series connected switches 44, 56, and a solenoid 45 connected in shunt 
with a load Z such as a tape driving motor or record/playback amplifier 
connected between the source E and the switch 44. The switch 44 has a make 
contact while the switch 56 has a break contact. The switch 44 is turned 
on when the cassette 16, as inserted into the holder 15, reaches the 
position of FIG. 6 as a result of the drive from the motor 20 and holder 
drive mechanism 22. At this time, the circuit is completed to energize the 
solenoid 45 and the load Z from the source E. The energization of the 
solenoid 45 is effective to operate a mechanism, not shown, which causes 
the pinch roller 46 and a magnetic head (not shown) to move into contact 
with the tape contained in the cassette 16 for record/playback operation. 
As mentioned previously, the load Z represents a record/playback amplifier 
or motor, and is maintained energized when the switch 44 is turned on. 
What has been described above is the operation which occurs when the 
cassette 16 is inserted. Considering now the operation which occurs when 
the cassette 16 which has been inserted as shown in FIG. 6 is removed, it 
is initiated when the eject button 52 is depressed downward. Thereupon, 
the other end 58 of the eject lever strikes against the bottom surface of 
the cassette holder 15, thus driving it upward. This upward drive is 
transmitted through the holder drive mechanism 22 to the shaft ends 20a, 
20a' of the motor 20, which therefore starts to rotate. Thus, as the 
cassette holder 15 is driven upward, the drive is transmitted through the 
pins 32, 32' to move the timing belts 26, 26' in opposite directions from 
those indicated by arrows w1, w1' shown in FIG. 4, whereby the gear pairs 
23, 23'; 28, 28' rotate clockwise while the gear pair 30, 30' rotates 
counter-clockwise. The counter-clockwise rotation of the gear pairs 30, 
30' imparts a counter-clockwise starting drive to the shaft ends 20a, 20a' 
of the brushless motor 20, which therefore immediately rotates in the 
counter-clockwise direction. As the motor 20 rotates in this manner, the 
drive therefrom is transmitted through the holder drive mechanism 22 to 
move the cassette holder 15 along the guide slots 36, 36', initially 
upward and then forwardly, thus moving it from the loaded position shown 
in FIG. 6 to the cassette insertion position shown in FIG. 2. When the 
cassette holder 15 reaches the position shown in FIG. 2, the guide slots 
36, 36' terminate, and hence the holder 15 cannot continue to move any 
further and thus comes to a stop. The stop causes a braking effort to be 
applied to the shaft ends 20a, 20a' of the motor through the holder drive 
mechanism 22, thus causing the motor 20 to stop its rotation. In the 
manner mentioned above, the cassette holder 15 is moved from the loaded 
position shown in FIG. 6 to the insertion position shown in FIG. 2 where 
the cassette 16 carried by the cassette holder 15 is caused to project out 
of the opening 14 so that the free end thereof can be gripped by hand to 
remove it. During the eject operation, the switch 56 shown in FIG. 7 is 
opened in response to the depression of the eject button 52, thus 
deenergizing the solenoid 45 and the load Z such as an amplifier or a tape 
drive motor. When the solenoid 45 is deenergized, the pinch roller 46 and 
magnetic head move away from their positions abutting against the tape in 
the cassette 16, to their original positions. 
FIGS. 8 to 11 illustrate another embodiment of the invention which employ a 
holder drive mechanism 60 including a pair of holder drive arms 62, 62' 
which are substituted for the pair of endless belts 26, 26' used in the 
initial embodiment. Specifically, in a cassette loading device 100 
illustrated in FIGS. 8 to 11, a pair of engaging pins 32, 32' fixedly 
mounted on the outside of the lateral sidewalls of a cassette holder 15 
engage elongate slots 64, 64', respectively, which are formed in one end 
of a pair of holder driving arms 62, 62', the other end of which is 
integrally connected to the opposite ends of a connecting shaft 66, on 
which a pair of gears 68, 68' are integrally mounted. The gears 68, 68' 
are in meshing engagement with a pair of gears 30, 31' integrally mounted 
on the rotary shaft of a brushless motor 20, through a reduction gear 
train including a plurality of gears 70-74, 70'-74'. In this manner, the 
drive from the motor 20 is transmitted to the arms 62, 62', or the 
movement of the arms 62, 62' is transmitted to the motor shaft. Components 
other than the arms 62, 62', the shaft 66, gear pairs 68, 68'; 70-74, 
70'-74' remain the same as those illustrated in the loading device 10 
shown in FIGS. 1 to 7. As shown in FIGS. 9 and 11, the location of the 
motor 20 is lower than the position shown in the first embodiment and the 
eject lever 50 is formed with a notch 76 (see FIG. 11) in its arm remote 
from the eject button 52 to avoid interference with the connecting shaft 
66. 
The operation of the cassette loading device 100 is substantially similar 
to that of the cassette loading device 10 shown in FIGS. 1 to 7, the only 
difference being that the arms 62, 62' acting in place of the belts 26, 
26'. Initially, when a cassette is to be inserted, the cassette 16 is 
inserted into the holder 15 through the opening 14 as indicated in FIG. 9, 
and the cassette 16 is then further pushed inward to drive the holder 15, 
whereupon the latter moves inward along the guide slots 36, 36' and such 
movement is transmitted through the arms 62, 62' to the gears 68, 68' and 
thence through the gears 70-74, 70'-74' to the gears 30, 30' which are 
mounted on the rotary shaft of the motor 20, thus applying a starting 
drive thereto. In response thereto, the motor 20 immediately starts to 
rotate. The resulting rotation is oppositely transmitted through the gear 
pairs 30, 30'; 74-70, 74'-70'; 68, 68' to the arms 62, 62', driving the 
latter counter-clockwise as indicated by an arrow w2 (see FIG. 8). As a 
consequence, the cassette holder 15 is driven further inward along the 
guide slots 36, 36' as a result of their pins 32, 32' engaging the 
elongate slots 64, 64' formed in these arms 62, 62'. Subsequently, the 
holder 15 is driven downward until a loaded position shown in FIG. 11 is 
reached. As the cassette holder 15 reaches such position and becomes 
unable to move any further, a braking effort is applied to the rotary 
shaft of the motor 20, which therefore immediately ceases to rotate. 
When the cassette 16 which is loaded in this manner is to be removed, the 
eject button 52 is depressed to drive the cassette holder 15 slightly 
upward. Thereupon, this movement is transmitted through the pins 32, 32', 
the arms 62, 62', the gear pairs 68, 68'; 70-74, 70'-74'; 30, 30' to the 
rotary shaft of the motor 20, applying a starting drive thereto to cause 
the motor 20 to be set in motion. The resulting drive from the motor 20 is 
transmitted through the gear pairs 30, 30'; 74-70, 74'-70'; 68, 68' to the 
arms 62, 62', driving the arms 62, 62' clockwise. The rotation of the arms 
62, 62' is transmitted to the cassette holder 15 through the pins 32, 32', 
and consequently the holder can be moved from the loaded position shown in 
FIG. 11 to the cassette insertion position shown in FIG. 9. When the 
cassette holder 15 reaches the position shown in FIG. 9 and comes to a 
stop, a braking effort is applied to the motor 20, which therefore ceases 
to rotate. In other respects, the operation of the cassette loading device 
100 is similar to that of the loading device 10. 
As described above, in the cassette loading device of the invention, a 
brushless motor is used which is capable of immediately starting to rotate 
in response to an externally applied starting drive in a direction 
determined by such drive and is also capable of immediately stopping in 
response to an external braking effort applied. A movement of the cassette 
holder which carries the cassette therein is transmitted to the motor 
through the cassette drive mechanism, thus controlling the motor in both 
cassette loading and removing operations. It will be seen that no 
particular motor starting means is required. In addition, advantages are 
gained in that operating performance is improved and the construction is 
simplified, enabling it to be inexpensively manufactured and making it 
trouble free.