Disc loading apparatus for a front loading disc player

A disc loading apparatus for a disc player based on the front loading method is disclosed. Positioning ribs formed on the tray supporting steps of a tray holder are meshed during operation with rib guiding grooves which are formed on the bottom of a tray. Upper and lower carrying rollers which are closely contacted with a guide band, or a carrying gear which is closely contacted with a rack gear revolve in such a manner that the tray would enter into a tray holder stably and precisely, thereby making the tray run fast. Set rollers which are formed on the inside of the tray holder prevent the lifting of the tray, so that the tray would move more stably. Further, the upper and lower carrying rollers which are clad with rubber make the movement of the tray more precise, as well as preventing the generation of noise in the meshing portions.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a disc loading apparatus for disc player. 
More specifically, the present invention relates to a front loading type 
disc loading apparatus in which a tray to mount a disc such as an optical 
video disc, a digital audio disc or a compact disc is horizontally moved 
into the disc player, and then, the disc is loaded onto a turntable in a 
vertical direction. 
2. Description of the Prior Art 
A disc player is for recording and reproducing data on a disc such as an 
optical video disc, a digital audio disc or a compact disc, on which a 
magnetic or optical recording can be carried out. There are many kinds of 
apparatus for loading and unloading a disc to and from the disc player. Of 
them, the most frequently used one is the front loading type disc loading 
apparatus in which a tray for mounting a disc is horizontally moved into 
the disc player, and then, the disc is loaded onto a turntable in a 
vertical direction. 
One of these conventional front loading type disc loading apparatuses is 
provided with a cylindrical roller inserted into a guide groove of a side 
of the tray, so that the tray for mounting a disc would move horizontally 
and stably along the groove. This disc loading apparatus is disclosed in 
U.S. Pat. Nos. 4,807,216 and 5,084,854. Meanwhile, another type is 
provided with a rack and revolving rollers, so that the rack and tray 
would be horizontally moved in a stable manner. This disc loading 
apparatus is disclosed in U.S. Pat. Nos. 4,794,583 and 4,825,429. 
Such conventional disc loading apparatus will be described in further 
detail referring to FIG. 1. 
A disc-mounting tray 10 is provided with a guide rib 14 on a side thereof 
in the lengthwise direction, i.e., in the tray carrying direction. A base 
plate 12 which is located below the tray 10 is provided with a guide 
groove 15 on a side wall thereof in the lengthwise direction, i.e., in the 
tray carrying direction corresponding with guide rib 14. Thus guide rib 14 
is movably inserted into guide groove 15. Meanwhile, the other side of the 
tray, on which guide rib 14 is not formed, is provided with a rack gear 
11. Rack gear 11 is coupled with a driving means 13 which is installed at 
a corresponding position upon base plate 12. Driving means 13 consists of 
a loading motor 16, a transmitting gear 17 and a carrying gear 18, 
carrying gear 18 being coupled with loading motor 16 and transmitting gear 
17. Carrying gear 18 and rack gear 11 of tray 10 are meshed together, and 
therefore, when loading motor 16 revolves, tray 10 moves straightly 
forward and backward in accordance with the revolution direction of 
loading motor 16. Such straight motions of tray 10 are stably maintained 
by guide groove 15 (formed on a side of base plate 12) and by guide rib 14 
of tray 10. 
However, in this conventional disc loading apparatus, there is a tolerance 
in the meshing between guide rib 14 of tray 10 and the guide groove of 
base plate 12. Therefore, the forward and backward movements of tray 10 
are not precise. Further, rack gear 11 of tray 10 and carrying gear 18 of 
driving means 13 are all made of a synthetic resin, and therefore, when 
they actuate being meshed together, they generate noise. 
SUMMARY OF THE INVENTION 
The present invention is intended to overcome the above described 
disadvantages of the conventional techniques. 
Therefore it is an object of the present invention to provide a disc 
loading apparatus in which the forward and backward movements of the tray 
and the consequent disc loading operation are more accurately carried out 
owing to the unique geometric configuration of the tray and the base 
plate. 
In achieving the above object, the present invention provides a disc 
loading apparatus which comprises: 
a tray for mounting a disc, and including a pair of steps formed in 
parallel with each other by being bent outward from the lower edges of the 
tray, one or more of rib guiding grooves being formed on the bottoms of 
the steps in the lengthwise direction thereof; 
a tray holder for allowing the tray to run through it, and including a pair 
of tray supporting steps formed in parallel with each other by being bent 
inward from the lower edges of the tray holder, positioning ribs being 
formed on the upper faces of the tray supporting steps in the lengthwise 
direction, the positioning ribs being meshed with the rib guiding grooves; 
a guide band portion formed on the outer face of a side wall of the tray in 
parallel with one of the steps keeping a distance from the steps, and 
extending a certain distance in parallel with the step, the front and rear 
ends of the guide band portion being bent down to contact with the step; 
and 
a carrying means for being driven by a driving means in a close contact 
with the upper and lower faces of the guide band portion. 
In this case, carrying means preferably consists of upper and lower 
carrying rollers. The tray holder preferably is provided with set rollers 
at positions on the inside of the side wall opposite to the guide band 
portion so as to prevent the lifting of the tray during the carrying of 
the tray within the tray holder, and the supporting step of the tray 
holder with the carrying means installed thereon preferably is provided 
with an inner wall formed by being bent upward from the inner edge of the 
step, a friction reducing projection being formed on the inner face of the 
inner wall in the lengthwise direction. 
The carrying means of the disc loading apparatus, e.g., the upper and lower 
carrying rollers, are clad with rubber. 
In achieving the above object, the present invention provides a disc 
loading apparatus which comprises: 
a tray for mounting a disc, and including a pair of steps formed in 
parallel with each other by being bent outward from the lower edges of the 
tray, one or more of rib guiding grooves being formed on the bottoms of 
the steps in the lengthwise direction thereof; 
a tray holer for allowing the tray to run through it, and including a pair 
of tray supporting steps formed in parallel with each other by being bent 
inward from the lower edges of the tray holder, positioning ribs being 
formed on the upper faces of the tray supporting steps in the lengthwise 
direction, the positioning ribs being meshed with the rib guiding grooves; 
and 
a rack gear integrally formed on the upper face of one of the steps of the 
tray for being meshed with a carrying gear, the carrying gear being 
rotated by a driving means. 
To solve still further the above problems, the rack gear and the carrying 
gear of the disc loading apparatus are also clad with rubber. 
Position ribs which are formed on the tray supporting step of the tray 
holder is engaged with rib guiding grooves which are formed on the bottom 
of the tray during operation. Further, upper and lower carrying rollers 
which are closely contacted with the guide band, or a carrying gear which 
is closely contacted with a rack gear revolve in such a manner that the 
tray would slide into or out a tray holder thereby making the tray run 
stably and precisely through the tray holder. Further, set rollers which 
are formed on the inside of the tray holder prevent the lifting of the 
tray, so that the tray will move more stably. Further, the upper and lower 
carrying rollers which are clad with rubber make the movement of the tray 
more precise, as well as preventing the generation of noise in the 
engaging portions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Hereinafter, the disc load player according to the present invention will 
be described in details with reference to the accompanying drawings. 
Embodiment 1 
FIG. 2 is an exploded perspective view showing a first embodiment of the 
present invention. 
Reference numeral 120 indicates a tray on which a disc is mounted. 
Reference numeral 130 indicates a tray holder which tray 120 passes 
through to move horizontally forward and backward. Steps 141 and 142 are 
formed by being outwardly bent in a parallel form on the opposite sides of 
tray 120, while tray supporting steps 144 and 145 are formed by being 
inwardly bent from the lower ends of the opposite sides of tray holder 
130. On tray supporting steps 144 and 145, there are provided positioning 
ribs 154 and 155, while on the bottom of the steps 141 and 142 of tray 
120, there are provided rib guide grooves 151 and 152 which are engaged 
with positioning ribs 154 and 155. Further, the edge of tray supporting 
step 145 is upwardly bent so as to form an inner wall 146 on which a 
projected portion 156 is formed. The positioning ribs may be provided with 
as many as wanted, and so many rib guide grooves should be provided with. 
A guide band portion 170 is formed integrally with a side of tray 120 and 
kept a certain distance from step 142. Guide band portion 170 extends in 
parallel with step 142 over a certain distance, and the ends of guide band 
portion 170 are bent down to be in contact with step 142. That is, guide 
band portion 170 is formed integrally with the side of tray 120 and with 
step 142. 
Referring to the front sectional view of FIGS. 2, 3 and 4 rib guide grooves 
151 and 152 of steps 141 and 142 of tray 120 are engaged with position 
ribs 154 and 155 of supporting steps 144 and 145 of tray holder 130, so 
that tray 120 will be able to run within tray holder 
On the inside of supporting steps 145 of tray holder 130 corresponding to 
the position of guide band portion 170, there is set a first carrying 
limiting position, and a first limit switch 182 is installed on the 
position. On the rear portion of the upper face of supporting step 145, 
there is set a second carrying limiting position, and a second limit 
switch 184 is installed on this position. Further, on the rear portion of 
supporting step 144 of tray holer 130, there in integrally formed a 
stopper 180. 
An upper carrying roller 190a and a lower carrying roller 190b are made to 
closely contact with guide band portion 170 by being connected with a gear 
shaft supporting boas 196, so that tray 120 may be able to move forward 
and backward when driven by a loading motor 191. 
As shown in FIGS. 3 and 4, on a side wall of tray holder 130, there is 
formed an insertion hole 195 corresponding with the positions of the upper 
and lower carrying rollers which are installed within guide band portion 
170. A gear shaft 197 which is extended to gear shaft supporting boss 196 
which is connected to carrying rollers 190a and 190b is inserted into 
insertion holes 195. Further, an oilless bearing 193 is installed within 
insertion hole 195. Further, the outer end of gear shaft 197 is coupled 
with a shaft insertion boss 198 which is projected on a pulley 194. On the 
circular surfaces of the front and rear ends of carrying rollers 190a and 
190b, there are formed friction reducing projections 192 for reducing the 
frictions which are generated in relation with the gear shaft supporting 
boss during its revolutions. The surfaces of upper and lower carrying 
rollers 190a and 190b are clad with rubber, thereby forming a disc loading 
apparatus. 
As shown in FIG. 2, at a position of the inner face of the side wall of 
tray holder 130 corresponding with the other side wall opposite to guide 
band portion 170, there is installed a set roller 158, so that when the 
tray is carried within the tray holder, the lifting of the tray would be 
pressed down. The set roller may be installed as many as desired along the 
side wall of tray holder 130. 
The disc loading apparatus of the first embodiment of the present invention 
constituted as above will now be described as to its operations. 
FIG. 3 is a front sectional view showing tray 120 of FIG. 2 inserted into 
tray holder 130. When a disc is to be loaded into a disc player, the user 
presses an eject switch (not shown) provided on the front of the player 
body, so as to insert a disc into the player. Then loading motor 191 which 
is electrically connected with the eject switch is driven in a certain 
direction. Then pulley 194 is driven counterclockwise. Therefore, as shown 
in FIGS. 4 and 5, upper carrying roller 190a which is coupled with pulley 
194 is rotated counterclockwise so as to push the upper face of the guide 
band portion forward (leftward in FIG. 5). At the same time, lower 
carrying roller 190b which is press-contacted with upper carrying roller 
190a is rotated clockwise so as to push the lower face of guide band 
portion 170 forward, thereby carrying the tray forward. 
Under this condition, tray 120 is carried forward by being guided by 
positioning ribs 154 and 155 which are inwardly bent from the opposite 
lower ends of tray holder 130. Under this condition, set rollers 158 which 
are installed on the side wall of tray holder 130 corresponding with guide 
band portion 170 press down step 141 of tray 120, so that the tray lifting 
phenomenon which is caused by the loading motor acting only on one side of 
tray 120 would be prevented. Thus when the forwardly moving tray 120 
arrives at the limit switch, i.e., at the front carrying limiting position 
formed at the outer side wall of tray holder 130 (on the side where guide 
band portion 170 is formed), the rear inner face of guide band portion 170 
of tray 120 activates limit switch 182, so that loading motor 191 will 
stop, and the forward carrying of tray 120 will be stopped. 
Thus, in a state with tray 120 stopped, the user may load or replace a 
disc, and push in tray 120 again. Then loading motor 191 is driven in the 
opposite direction, and thus, pulley 194 and upper and lower carrying 
rollers 190a and 190b are rotated in the opposite direction. Thus the 
disc-mounting tray is carried into the disc player by being guided by the 
positioning ribs 154 and 155, while set rollers 158 prevent the lifting of 
tray 120. Thus when tray 120 which is being carried backward arrives to 
rear limit switch 184, i.e., the rear carrying limiting position of the 
upper rear end portion of supporting step 145 of tray holder 130 (on which 
guide band portion 170 is formed), the rear end of tray step 142 activates 
rear limit switch 184, so that the driving of loading motor 191 will be 
stopped, and the backward carrying of tray 120 will be stopped. Under this 
condition, tray 120 is prevented from a backward departure by stopper 180 
which is integrally formed on the rear end portion of supporting step 344 
of tray holder 130. 
Thus when tray 120 is stopped at the predetermined position within the 
player body, for example, the spindle assembly including the turntable is 
elevated and clamped, that the disc will revolve through the selection of 
the play mode, and a feeding is made. 
According to the first embodiment of the present invention, the following 
effects are obtained. That is, the tray carrying operation is precisely 
done owing to: the positioning ribs of the tray supporting steps (which 
are inwardly bent from the lower ends of sides of the tray holder); the 
rib guide grooves engaged with the positioning ribs and formed on the 
bottom of the steps (which are outwardly bent from the lower side ends of 
the tray); the upper and lower carrying rollers which are installed in a 
close contact with the upper and lower faces of the guide band portion; 
and the set rollers which are fixedly installed on the inside of the side 
wall of the tray holder. Further, the upper and lower carrying rollers 
which are clad with rubber are rotated in a close contact with the upper 
and lower faces of the guide band portion so as to carry the tray 
including the guide band portion forward and backward, and therefore, 
noise is not generated from the meshed portions during the carrying. 
Embodiment 2 
Now a second embodiment of the present invention will be described. 
FIG. 6 is an exploded perspective view showing a second embodiment of the 
present invention. 
Reference numeral 220 indicates a tray on which a disc is mounted. 
Reference numeral 230 indicates a tray holder which tray 220 passes 
through to move horizontally forward and backward. Steps 241 and 242 are 
formed by being outwardly bent in a parallel form on the opposite sides of 
tray 220, while tray supporting steps 244 and 245 are formed by being 
inwardly bent from the lower ends of the opposite sides of tray holder 
230. On tray supporting steps 244 and 245, there are provided positioning 
ribs 254 and 255, while on the bottom of steps 241 and 242 of tray 220, 
there are provided rib guide grooves 251 and 252 which are engaged with 
positioning ribs 254 and 255. Further, the edge of tray supporting step 
245 is upwardly bent so as to form an inner wall 246 on which a projected 
portion 256 is formed. The positioning ribs may be provided with as many 
as wanted, so many rib guide grooves should be provided. 
A rack gear portion 270 is integrally formed along a bent line on the upper 
face of step 242 of the tray. 
Referring to the assembled frontal sectional view of FIG. 7, rib guide 
grooves 251 and 252 of steps 241 and 242 of a tray 220 are meshed with 
positioning ribs 254 and 255 of a tray holder 230, so that tray 220 will 
be able to smoothly run within tray holder 230. 
Further, a third carrying limiting position is set on the front portion of 
the inside of an inner wall 246 of supporting step 245 of tray holder 230 
corresponding with rack gear portion 270. At the third carrying limiting 
position, there is installed a third carrying limit switch 282. Further, a 
fourth carrying limiting position is set on the rear portion of the upper 
face of supporting step 245, at which a fourth carrying limit switch 284 
is installed. Further, a switch actuation piece 286 is installed on the 
rear portion of the inner side wall of tray 220 on which rack gear portion 
270 is formed. Further, a stopper 280 is integrally formed on the rear 
portion of supporting step 244 of tray holder 230. 
A carrying gear 290 is installed on tray holder 230, so that carrying gear 
290 will be meshed with rack gear portion 270 of tray 220, and that tray 
220 will move forward and backward in accordance with the driving of 
loading motor 291. 
As shown in FIGS. 7 to 9, a gear shaft 297 which is extended to gear shaft 
supporting boss 296 which is connected to carrying gear 290, and gear 
shaft 297 is inserted into insertion hole 295. Further, an oilless bearing 
293 is installed within insertion hole 295. Further, the outer end of gear 
shaft 297 is coupled with a shaft insertion boss 298 which is projected on 
a pulley 294. On the circular surfaces of one end of gear shaft supporting 
boss 296, there are formed friction reducing projections 292 for reducing 
the frictions which is generated in relation with the gear shaft 
supporting boss during its revolutions. 
Further, rack gear portion 270 and/or carrying gear 290 are clad with 
rubber. 
As shown in FIG. 6, at a predetermined position on the inside of a side 
wall of tray holder 230 corresponding with the side wall opposite to rack 
gear portion 270, there is fixedly installed a set roller 258 so that the 
lifting of tray 220 during its carrying within the tray holder will be 
prevented. Set rollers 258 may be installed with as many as desired along 
the side wall of tray holder 230. 
The second embodiment of the present invention constituted as above will 
now be described as to its operations. 
FIG. 7 is a frontal sectional view showing tray 220 and tray holder 230 of 
FIG. 6 assembled together. When a disc is to be loaded into the disc 
player, first the user pushes an eject switch (not shown) which is 
provided on the front face of the player body. Then a loading motor 291 
which is electrically connected to the eject switch is driven. Then a 
pulley 294 is rotated clockwise. Accordingly, as shown in FIGS. 8 and 9, 
carrying gear 290 which is coupled with pulley 294 is rotated clockwise, 
so that rack gear portion 270 which is engaged with the carrying gear will 
be pushed forward, and tray 220 will be carried forward. Then tray 220 is 
carried forward by being guided by the positioning ribs 254 and 255 of 
tray supporting steps 244 and 245 which are formed by being bent inward 
from the lower ends of tray holder 230. At the same time, set rollers 258 
which are fixedly installed on the side wall of tray holder 230 opposite 
to rack gear portion 270 press down step 241 of tray 220, so that the 
lifting of the tray due to the action of the loading motor to one side of 
the tray will be prevented. Thus when tray 220 arrives at the front limit 
switch 282, i.e, at the front carrying limiting position of the inside of 
the inner wall of tray holder 230, switch actuation piece 286 of the 
inside of the side wall of tray 220 activates limit switch 282 of tray 
holder 230, so that the driving of loading motor 291 will be stopped, and 
the forward carrying of tray 220 will be stopped. 
Thus, the user can load a disc or replace a disc, and then, may push tray 
220 into the player body. Then loading motor 296 is driven in the opposite 
direction, and pulley 294 and carrying gear 290 are rotated in the 
opposite direction, i.e., counterclockwise. Thus the tray 220 on which a 
disc is loaded is carried backward, i.e., into the player body by being 
guided by positioning ribs 254 and 255. Under this condition, set rollers 
258 prevent the lifting of tray 220. 
When the tray which is being carried backward arrives at rear limit switch 
284, i.e., at the rear carrying limiting position of supporting step 245 
near rack gear portion 270, the rear end of tray step 242 activates rear 
limit switch 284, so that the driving of loading motor 291 will be 
stopped, and that the backward carrying of tray 220 will be stopped. Under 
this condition, tray 220 is prevented from a backward departure owing to 
stopper 280 which is integrally formed with the rear end portion of 
supporting step 244 of tray holder 230. 
According to the second embodiment of the present invention as described 
above, the tray carrying operation is precisely done owing to: the 
positioning ribs formed on the tray supporting step inwardly bent from the 
lower edges of the opposite walls of the tray holder; the rib guiding 
grooves formed on the bottom of the steps outwardly bent from the lower 
edges of the opposite walls of the tray, the positioning ribs being 
engaged with the rib guiding grooves so as to make the tray run; the rack 
gear portion and the carrying gear engaged with it and the set rollers 
installed on the inside of one side wall of the tray holder. Further, the 
rack gear portion and/or the carrying gear which are engaged together are 
clad with rubber, and therefore, when the tray moves back or forth, noise 
is not generated from the meshed portions, thereby improving the product 
quality. 
While the present invention has been particularly shown and described with 
reference to particular embodiments thereof, it will be understood by 
those skilled in the art that various changes in form and details may be 
effected therein without departing from the spirit and scope of the 
invention as defined by the appended claims.