Door opening and closing mechanism for disc driving apparatuses

A door opening and closing mechanism for disc driving apparatuses, comprising a chassis, a frame fastened pivotably to the chassis and having a door member holding portion at a free end thereof, a door member consisting of a cross-sectionary L-shaped operating portion with projections on both side surfaces thereof, and a mounting portion slidably held in the door member holding portion of the frame. A coiled spring is provided between pivotable frame and door member so as to constantly urge the door member against a rear surface of a front panel, and the projections provided on the operation portion of the door member are engageable with recesses in the back surface of a front panel. An elongated opening is provided in the front panel and receives a disc cartridge thereinto, the elongated opening being opened and closed by and with the door member. The mechanism has fewer parts than the conventional mechanism, and can be manufactured efficiently at a lower cost.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a door opening and closing mechanism for disc 
driving apparatuses. 
2. Description of the Prior Art 
The conventional door opening and closing mechanism for a disc drive 
apparatus typically includes an operating button for opening a door 
member, and a separate locking member for maintaining the door member in a 
closed state. Such mechanisms typically requires a plurality of parts 
which leads to inefficiencies in assembly and also complicates the door 
opening and closing operations. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide an inexpensive door 
opening and closing mechanism for disc driving apparatuses, which enables 
the door opening and closing operations to be carried out simply, and 
which has fewer parts and a more simple construction than conventional 
mechanisms. 
The above and other objects as well as advantageous features of the 
invention will become apparent from the following description of the 
preferred embodiment taken in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
An embodiment of the present invention will now be described with reference 
to the drawings. Reference numeral 1 denotes a front panel molded out of a 
synthetic resin. The front panel 1 is provided with an elongated opening 
4, into which a disc cartridge 2 containing a flexible magnetic disc 3 can 
be inserted. The front panel 1 is further provided substantially in the 
central portion thereof with an opening 6, in which a door member 5 for 
restricting the action of inserting the disc cartridge 2 is positioned. 
(Refer to FIG. 1a.) Reference numeral 7 denotes a recess in the front 
panel for receiving fingers to enable the door member to be operated 
easily. A display lamp 8 is provided in the front panel for indicating the 
operational condition of a means for driving the flexible magnetic disc 3, 
and a chassis 9 is formed by punching a metal plate, and bending the 
punched product. The chassis 9, front panel 1, and two side panels 10, 11 
molded out of a synthetic resin constitute a casing. 
The door member 5 is made of a synthetic resin, and, as shown in FIG. 2, 
consists of an L-shaped operating portion 12 and a mounting portion 13. 
Extending laterally outwards from the sides of the operating portion 12 on 
both sides thereof with projections 14 for regulating the door opening and 
closing operations. The mounting portion 13 is provided with an opening 16 
receiving a coiled spring 15 for urging the door member 5 toward the front 
panel, and a projection 17 as provided in the opening 16 for receiving the 
coiled spring 15. A pivotable frame 18 formed from a metal plate has the 
door member 5 and a disc holder 19 mounted thereto. The pivotable frame 18 
is provided with pivotable supports 20 at one end portion thereof, an 
opening 21, an arm 22, a door member-holding portion 23 at its other end, 
holding members 24 extending laterally from respective longitudinal sides 
of the pivotable frame 18, and a mount 25 for holding a sector detecting 
optical semiconductor element. (Refer to FIG. 2.) The door member holding 
portion 23 of the pivotable frame 18 is capable of holding the mounting 
portion 13 of the door member 5, and is provided with a recess 26 
corresponding with the recess 16 for receiving the coiled spring 15, and a 
projection 27 at an inner end of the recess 26. A projection 27 is 
provided at the other end of the recess 26 and the coiled spring 15 can 
thus be compressed between the projections 17 and 27 to urge the door 
member 5 leftwardly in FIG. 2. The frame 18 is connected pivotably to the 
chassis 9 via pins through the supports 20, and the end portion of the 
frame 18 adjacent the door member 5 is urged upwardly at a predetermined 
angle with respect to the surface of the chassis 9 by a U-shaped spring. 
Referring to FIG. 5 a disc holder 19 formed of a synthetic resin is 
fastened rotatably to the pivotable frame 18. The disc holder 19 is 
provided in a circumferential surface thereof with a plurality of 
regularly-spaced slots extending inward in the radial direction so as to 
form a plurality of arms 28. Each of these arms has a sufficiently high 
resilient force and is provided on the inner surface thereof with a 
projection 29, which extends toward the center of the disc holder 19, and 
has an inner portion with a downwardly sloping upper surface. As shown in 
FIG. 11(a) illustrating the assembled disc holder in section, the disc 
holder 19 has a flat wall portion 30 adapted to extend generally coplanar 
to the the flexible magnetic disc 3 for supporting the disc, an inclined 
guide wall portion 31, and a bottom wall 32. A support member 33 is 
mounted on a shaft 35 via a bearing 34. The support member 33 is provided 
in the outer circumferential surface thereof with a groove 36 which 
receives the tapering free end portions of the projections 29 of the disc 
holder 19 to join the disc holder 19 to the support member 33. A washer 
and a plate spring 37 are placed around the shaft 35, and an E washer on 
the other side thereof to fix the disc holder 19 to the pivotably frame 
18. As shown in FIG. 6, a mechanism for discharging a disc from the device 
includes a substantially L-shaped movable discharge member 40, a receiving 
block 41 formed from a synthetic resin, in which the discharge member 40 
is slidingly received, a holding member 42 for constantly retaining the 
movable discharge member 40 within the receiving block 41, and a coiled 
spring 43 shown in FIG. 10(a) which is adapted to urge the movable 
discharge member constantly downward. 
A head carriage positioned substantially in the opening 21 of the pivotable 
frame 18 includes a base 45, to which a head 44 for carrying out writing 
and reading operations is fixed, and a movable member 47, carrying a pad 
46 for pressing the flexible magnetic disc 3 against the head 44 is. 
Reference numeral 70 denotes a spring for urging the movable member 47 
constantly toward the base 45. The base 45 is provided with guide portions 
45b having guide bores 45a, through which a guide shaft 48 is inserted, 
and mounting portions 45d having respective bores 45c, through which a pin 
49 for fastening the movable member 47 to the base 45 is inserted. The 
movable member 47 is provided with a long, narrow arm 47a, and mounting 
portions 47b by which the movable member 47 is fastened to the base 45. 
A head carriage driving mechanism has as a driving power source therefor a 
stepping motor 50 attached to a rear surface of the chassis 9. Reference 
numeral 51 denotes a pulley mounted directly on a rotary shaft 50a of the 
stepping motor 50. A belt 52 consisting of a thin metal strip is passed 
around the pulley 51, and fixed to the same with screws. Reference numeral 
53 denotes another pulley rotatably fixed to a mount 54, and the belt 52 
is also passed around the pulley 53. The mount 54 is formed substantially 
in the shape of the letter "L", and is provided with a bore for movably 
fixing the mount 54 around the shaft, and an engaging portion 54a for use 
in fastening thereto one end of a coiled spring 55, by which the mount 54 
is drawn in one direction. Owing to the resilient force of the coiled 
spring 55, the endless belt 52 wrapped around the pulleys 51, 53 is kept 
constantly taut, so that there is no slack in belt 52. The belt 52 is 
provided with a bore, into which a projection 45e extending from the free 
end of the guide portion 45b of the base 45 is inserted. When the stepping 
motor 50 is energized, the pulley 51 rotates causing the belt 52 to move, 
and the head carriage is moved accordingly. 
A pair of guide shafts 48 slidably supporting the head carriage are set on 
projections 56 formed by bending the chassis 9. The guide shafts 48 are 
then pressed downward by holding members 57, which are fixed with screws 
58. The guide shafts 48 are thus rigidly held to the chassis 9. 
Reference numeral 59 denotes a micro-switch provided on the chassis 9 at a 
location s0 that an operating member 59a carried by a projection 45f. 45b 
of the base 45 may be slidingly moved into a slot of the micro-switch. A 
dc motor 60 is provided on the upper side of the chassis 9 for driving via 
a driving belt 62 shown in FIG. 4 a rotary plate 61 attached to a driving 
hub 63, to rotate the flexible magnetic disc 3. 
Reference numeral 64 denotes a disc pressing member formed by bending a 
resilient metal plate, for example, a phosphor bronze plate. The disc 
pressing member 64 is pivoted by a plunger 66, which is driven by an 
electromagnetic solenoid 65. A resilient member 67, a sponge, for example, 
is glued onto the portion of the member 64 by which the disc cartridge 2 
containing a flexible magnetic disc therein is pressed. Reference numeral 
68 denotes a writing prevention detecting mechanism positioned in the 
vicinity of the side panel 11. 
The operations for opening and closing the door member 5 will be now 
described with reference to FIGS. 9(a) and 9(b). The door member 5 joined 
to the pivotable frame 18 is constantly urged in the direction of an arrow 
A by the coiled spring 15 with a pivotal force being applied to the frame 
18 in the direction of an arrow B by the resilient force of a U-shaped 
spring at the pivotal connection 20. When the operating portion 12 is 
moved in the direction of an arrow C against the force of the U-shaped 
spring with the door member 5 in an opened state as shown in FIG. 9b, the 
projections 14 provided on the operating portion 12 are moved along the 
rear surface of the front panel 1, and the mounting portion 13 of the door 
member 5 gradually moves inwardly against the force of the coiled spring 
15 into the door member-holding portion 23 of the pivotable frame 18. When 
the projections 14 of the operating portion 12 have reached the portion of 
the rear surface of the front panel 1 which corresponds to the recess 26, 
the door member 5 is moved in the direction of the arrow A due to the 
force of the coiled spring 15, so that the projections 14 engage the 
recess 26 to hold the pivotable frame 18 in a portion more parallel to the 
plane of the disc inserted in the device. When the operating portion 12 of 
the door member 5 is pushed inwardly with the door member 5 in the 
condition shown in FIG. 9a, the projections 14 are disengaged from the 
recess 26, and the frame 18 can pivot in the direction of the arrow B due 
to the force of the U-shaped spring to return to the position shown in 
FIG. 9b. 
The operation of the mechanism for discharging a flexible magnetic disc 
will be described in detail with reference to FIG. 10. When the disc 
cartridge 2 is inserted into the elongated opening 4 in the front panel 1 
with the door member 5 opened, it is guided by grooves provided in the 
inner surfaces of the side panels 10 and 11, and a rear end portion of the 
cartridge 2 then comes into engagement with the bent portion 40b of the 
movable discharge member 40. (FIG. 10a) When the disc cartridge 2 is 
further moved, the discharge member 40 is moved (FIG. 10b) against the 
force of the coiled spring 43. When the forward end portion 40a of the 
discharge member 40 has passed by stepped portion 41a, the end portion 40a 
drawn downward by the coiled spring 43 and is urged against the stepped 
portion 41a, while the bent portion 40b at the other end of the discharge 
member 40 is moved slightly upward to engage the end portion 22a of the 
arm 22 fastened to the pivotable frame 18. (Refer to FIG. 10c) The 
operation for inserting the disc cartridge 2 into the opening 4 is thus 
completed. When the door member 5 then pivots and is closed, the arm 22 
provided on the pivotable frame 18 is moved to cause the bent portion 40b 
of the movable discharge member 40 to be pressed downward by the end 
portion 22a of the arm 22. Consequently, the end portion 40a is lifted 
upward and moves forward slightly to become disengaged from the stepped 
portion 41a of the receiving block 41, and the movable discharge member 40 
is kept in the condition shown in FIG. 10d. When the door member 5 is 
closed, the flexible magnetic disc 3 is held by the driving hub 63 and 
disc holder 19, so that writing or reading operation from the head 44 is 
ready to begin. When the door member 5 pivots after writing or reading of 
data has been completed, the door member 5 is opened, and the frame 18 
also pivots at the same time, so that the arm 22 moves in the direction of 
the arrow D. Consequently, the free end portion 22a of the arm 22 and the 
bent portion 40b of the movable discharge member 40 are disengaged from 
each other, so that discharge member 40 is moved rapidly in the direction 
of the arrow E due to the force of the coiled spring 43 to discharge the 
disc cartridge 2 out of the door opening and closing mechanism. 
The mechanism for holding a flexible magnetic disc will now be described in 
detail with reference to FIGS. 11(a) and 11(b). When the frame 18 is moved 
pivotally with a central hole in the flexible magnetic disc 3 positioned 
between the disc holder 19 and driving hub 63, the disc holder 19 fastened 
to the frame 18 is moved, and the inclined guide wall 31 of the disc 
holder 19 begins to enter the hole in the disc 3. The disc holder 19 is 
inserted into the hole in the disc as the position of the disc 3 is 
corrected by the inclined surfaces of the guide wall 31. Since the disc 
holder 19 and a recess 63a in the driving hub 63 are positioned directly 
opposite each other, the holder 19 is inserted accurately into the hub 63. 
A projection 69 provided in the center of the recess 63a in the driving 
hub 63 comes into contact with the center of the bottom wall 32 of the 
disc holder 19. When the disc holder 19 is further moved downward, the 
center of the bottom wall 32 is pressed, so that the disc holder 19 is 
deformed within the range of elasticity thereof. Namely, the arms 28 are 
flexed in such a manner that they expand slightly outward. As shown in 
FIG. 11b, the expanding arms 28 of the disc holder 19 can press against 
the side walls of the hole in the disc 3 so as to forcibly engage the 
disc, and the disc supporting wall 30 presses the disc 3 against an upper 
surface 63b of the driving hub 63. Thus, the flexible magnetic disc 3 is 
held securely by the disc holder 19 and driving hub 63. This allows the 
rotation of the DC motor 60 to be transmitted accurately to the disc 3 via 
the driving hub 63. 
An operation for driving the carriage consisting of the base 45 provided 
with the head 44, and movable member 47 provided with the pad 46 will be 
described. The base 45, to which the head 44 is fixed, is slidingly 
movable via the guide shafts 48, and adapted to be driven by the belt 52 
wrapped around two pulleys 51 and 53. The rotary shaft 50a of the stepping 
motor 50 is tightly fitted in the pulley 51. When the stepping motor 50 is 
rotated, the belt 52 fixed to the pulley 51 with screws is moved, and the 
base 45 is also moved therewith. Since tension of the belt 52 is 
constantly maintained by the coiled spring 55 as mentioned above via the 
pulley 53 freely joined to the mount 54, the base 45 can be moved 
accurately. A fan-shaped cam 51a engaged with a stopper 71 is formed on 
the pulley 51 so as to prevent the carriage from being moved too far. The 
operating member 59a for the micro-switch 59 is positioned on one side of 
a passage, in which a third guide portion 45f is moved. When the carriage 
is moved to a zero track position, the micro-switch 59 is operated to stop 
the movement thereof. The carriage can be moved by the stepping motor 50 
between the zero track position and 35 track position. 
The operations for writing and reading data in and from the flexible 
magnetic disc 3 by the head 44 provided on the carriage will be described. 
The disc cartridge 2 is inserted in a predetermined position with the door 
member 5 opened, and the door member 5 is then closed to hold the flexible 
magnetic disc 3 in a proper position by the disc holder 19 and driving hub 
63. The flexible magnetic disc 3 is rotated at 300 r.p.m. by the dc motor 
60. At this time, the disc 3 has not yet contacted the surface of the head 
44 on the base 45, said disc 3, however, is in a position very close to 
the surface of the head 44. Although the movable member 47 provided with 
the pad 46 is driven toward the base 45 by the spring 70, the long, narrow 
arm 47a is engaged at the free end portion thereof with the upper surface 
of the disc pressing member 64. Accordingly, the pad 46 is not in contact 
with the surface of the disc 3; it is poised above it (FIG. 12a). The 
electromagnetic solenoid 65 is excited by a head load signal to attract 
the plunger 66 thereto, so that the disc pressing member 64 is moved in 
the direction of an arrow F. When the disc pressing member 64 is moved 
toward the disc cartridge 2, the member 47 is moved in accordance 
therewith. The pad 46 provided on the movable member 47 comes into contact 
with the surface of the disc 3, which is brought into engagement with the 
surface of the head 44, as the disc cartridge 2 is lightly pressed by the 
elastic member 67 glued on the disc pressing member 64, to cause the disc 
in rotary motion to be pressed lightly thereby. Thus, the disc 3 can be 
kept in stable contact with the head 44. The data are then written in or 
read from the disc 3 by the head 44. When an head unload signal is 
generated after the writting or reading of data has been finished, the 
electromagnetic solenoid 65 de-energized, and the plunger 66 returns to 
the original position, so that the disc pressing member 67 is moved in the 
direction of the arrow G. At the same time, the movable member 47 is 
raised upward so that the pad 46 separates from the surface of the disc 3. 
Thus, the head 44 and disc 3 are separated. 
As described above, the door opening and closing mechanism for disc driving 
apparatuses according to the present invention includes a door member, a 
mounting portion of which is slidably held in a door member holding 
portion of a pivotable frame attached to a chassis, a spring provided 
between the pivotable frame and door member for constantly urging the door 
member against the rear surface of a front panel, and a recess provided in 
the rear surface of the front panel for receiving projections provided on 
an operating portion of the door member. When the operating portion is 
moved pivotally with the fingers, the door member can be opened and closed 
simply. Therefore, unlike the conventional door opening and closing 
mechanism, the present invention does not require an operating button for 
opening the door member, nor a locking member for maintaining the door 
member in a closed state. This allows the number of parts to be minimized, 
and the construction to be simplified. Therefore, the present invention 
permits providing an inexpensive door opening and closing mechanism for 
disc driving apparatuses, which can be efficiently assembled and has a 
very marked practical effect on operation. 
The present invention is not, or course, limited to the above embodiment; 
it may be modified in various ways within the scope of the appended claims 
.