DE19639378A1 - Cartridge loading mechanism used in cartridge interchanging type disc appts such as MO disk unit, optical disk appts, FD drive appts, MD appts - Google Patents

Abstract

The mechanism comprises a base plate (3) which supports a loading base part (18). An oscillating cam (24), on which a cartridge holder (22) and a carrier (23) are mounted, is set vibratably at the loading base part. The cartridge holder is used for insertion or removal of a cartridge which stores the recording medium. The carrier is arranged to the bottom part of the cartridge holder. The oscillating cam is arranged, so that the vertical movement of the cartridge holder is interlocked with the horizontal movement of the carrier along cartridge insertion or ejection direction. The movement of the cartridge holder is carried out by a spindle motor.

Description

The present invention relates to a cassette loading mechanism which in one Disc exchange type disk unit such as a magneto-optical one Disk unit of an optical disk unit, a floppy disk drive unit, one Mini disc unit, etc. is applied.

There is a system that uses a swing cam as a general example of one typical cassette loading mechanism of a magneto-optical disk unit or a magneto-optical disk unit is used. A goal of this cassette Loading mechanism is to ensure a dustproof design by the Cassette loading mechanism is constructed as a perfectly sealing structure. For example, this system using a swing cam is used in one  Loading mechanism used in Japanese Patent Application Laid-Open (KOKAI) No. 3-108154.

In accordance with this system, the cassette loading mechanism can be constructed if the swing cam with a play in the width direction between a basket body or a cover that forms the sealing structure forms, and a tray or a carrier is arranged. Therefore, the perfect sealing structure of the cassette loading mechanism can be achieved, without increasing the width of the disc unit.

With this system, the cassette loading mechanism can be compact in width direction. However, a space for the loading mechanism of the Bottom of the carrier to the top of the magnetic head needed, so that Drive unit can not be made thin.

In a technique described in the above Japanese Patent Application Laid-Open it is possible to achieve a stable cassette loading mechanism that is high Effectiveness regarding dust tightness with a small number of con has structural parts. However, it is necessary after the carrier and the cam were attached to the basket body, an operating shaft or an operating shaft the cam fit into a hole in the tray while the cam goes through the tray is bent outwards. At this time or at this stage, plastic or Plastic, such as polyacetal resin, used as a material in With regard to the lubricity. The thickness of this plastic is relatively low. Therefore, the cam is deformed when the cam deflection at this fitting time is left as it is (then). If a fitting scope (Extent of protrusion or protrusion) of the cam with respect to the tablet an effective axis or an actuation axis of the cam is reduced so that the Cam fits easily into the tray, an engagement circumference of the cam and the  Trays reduced. Therefore, the cam is removed from the tray during loading and Unloading operations of a cartridge are disengaged so that the cartridge is not can be loaded and unloaded exactly or exactly.

Another general technique described in Japanese Patent Publication (KOKOKU) No. 4-77396, a dustproof door is disclosed, the two Doors used. A second door opens in an opening direction at all times biased. A lever is lowered through a cassette when the cassette is installed or introduced. The second door is with one end tip of this lever engaged. Accordingly, the second door against biasing forces in the Opening direction closed. However, a finger goes through the second door pinched or squeezed if shortly after the cassette has been inserted, the finger is removed or removed from the cassette too late or hesitantly. At this time, the attack force to push the cassette down is one Preload force of a spring or the force of a motor. Accordingly, the Driving force considerably strong. Therefore, there is a risk of injury if the finger is pinched.

To solve this problem, the inventors of this patent application previously had one dustproof door mechanism proposed to close the second door in a to bias the direction at any time, as described in the patent description of the Japanese Patent Application Laid-Open (KOKAI) No. 7-201166.

However, in the case of Japanese Patent Application Laid-Open (KOKAI) No. 7-201166, the second door reliably biased in the closing direction at all times, only one There is force to close the second door itself. Accordingly, there is none serious problem in the above-mentioned Japanese patent publication (KOKOKU) No. 4-77396 is shown when a finger goes through the second door  pull out. However, a stroke of lowering a cassette at the time corresponds to to which it is inserted, proportional to a stroke for closing the second door. Therefore, closing the second door begins with the lowering of the Cassette. Accordingly, a finger gets through the second door just as easily pinched, as in the technique of Japanese Patent Application Laid-Open (KOKAI) No. 7-201166. There is also the problem of hurting the operator's feelings or to annoy him even though the operator was not injured. In contrast to corresponds to when the cassette is ejected from the cassette loading mechanism, a stroke for lifting the cassette similarly proportional to a stroke for Open the second door when the cassette is lifted up. So if unloading the cassette by spreading the unloading start time of the cassette Unloading mechanism begins before the cassette is completely up to the height of one Unloading position is raised, the cassette engages with the second door and it is not unloaded by the cassette unloading mechanism since the second door is not is completely open.

It is therefore an object of the present invention to provide a more secure and thinner cassette loading mechanism to solve the above problems deliver.

In accordance with the first construction of the following invention, the above object can be achieved by:
A cassette loading mechanism with:
a loading base;
a cassette holder for attaching a cassette that stores a storage medium therein;
a carrier for guiding the cassette holder to a predetermined position at an insertion or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base; and
a base plate for carrying or holding the loading base part; wherein the cassette loading mechanism is constructed such that the carrier is arranged on an upper side of the cassette holder, and
the swing cam is arranged such that the cassette holder is reciprocated vertically together with a reciprocating motion of the carrier in a direction approximately equal to an insertion / unloading direction of the cassette.

In accordance with the second construction of the present invention, the cassette loading mechanism further comprises:
an eject button for receiving or receiving a biasing force of the cassette in its insertion direction by means of an operating device or an operating tool from outside the cassette loading mechanism;
an eject lever having a hole portion in its central portion configured such that one end portion of the eject lever is connected to the eject button and the other end portion of the eject lever is engaged with the carrier to move the carrier in the unloading direction of the cartridge ;
a stepped pin which is attached to the loading base and rotatably supports the ejection lever through the hole portion; and
biasing means for biasing the eject lever so that the other end portion of the eject lever is rotated in a direction approximately equal to a moving direction of the carrier at a time when the cassette is being loaded;
the perforated portion being formed by a first perforated portion through which it is possible to pass a head portion of the stepped pin and a second perforated portion connected to the first perforated portion and fitted to a shaft portion of the stepped pin ; and
wherein the eject lever is attached to the stepped pin such that a direction directed from a center of the second hole portion to a center of the first hole portion approximately coincides with a biasing direction of the biasing means.

In accordance with a third construction of the present invention:
a lever pin is vertically attached to an end portion of the eject lever;
a hole for inserting the lever pin therein is formed in a portion of the eject button;
a groove portion is formed in a side surface of the eject button;
the groove portion of the eject button is engaged with the loading base; and
a holding portion is formed to slidably carry the ejection button along the insertion direction of the cartridge.

In accordance with a fourth construction of the present invention:
a front cover having a cassette insertion opening for inserting and removing the cassette is arranged in front of a cassette receiving opening of the cassette holder;
a first door for opening and closing the cassette insertion opening by a turning operation is arranged near this front cover;
the eject button is positioned after the first door when the cartridge is inserted into the cartridge insertion opening;
a small hole for inserting an operating tool or an operating device therein is formed in the front cover;
a contact portion for receiving an end tip of the actuating device or the actuating tool is formed in the eject button; and
a groove portion is formed on a portion of a virtual line connecting the small hole to the contact portion on a rear surface of the first door that comes into contact with the cartridge when the cartridge is inserted.

In accordance with a fifth construction of the present invention:
a screw holding portion for fixing the loading base is formed in each of four top corners of the base;
a first extension that comes into contact with an end tip of the cartridge is formed on a cartridge insertion side surface of the first door;
a position of this first extension is set to a position opposite to the screw retaining portion on a front side when the first door is fully opened at a cassette insertion or unloading time; and
a recess portion is formed on a back surface of the first extension.

In accordance with a sixth construction of the present invention, the object can also be achieved by:
a cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that stores a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at an inserting or discharging time of the cassette; and
a base plate for carrying or holding the loading base part;
wherein the cassette loading mechanism is constructed such that a first door for closing the cassette insertion opening is rotatably disposed in the vicinity of a front cover at a cassette unloading time;
wherein a second door for closing the cartridge insertion opening is slidably disposed in a direction perpendicular to a cartridge insertion / unloading direction at a cartridge loading time;
a lever for moving the second door by rotating this lever in association with movement of the bracket is arranged; and
a flexible or bendable section is formed in this lever.

In accordance with a seventh construction of the present invention, that: the flexible portion is formed in the shape of a leaf spring by a Constriction is formed in a section of the lever.

In accordance with an eighth construction of the present invention, that: the flexible portion is formed in the shape of a leaf spring by a Notch is formed such that the notch is a center of rotation of the lever from the outside or from the outside.

In accordance with a ninth construction of the present invention, the above object can also be achieved by:
a cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that receives a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at an insertion or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base; and
a base plate for carrying or holding the loading base part;
the cassette loading mechanism being constructed such that a first door for closing a cassette insertion opening is rotatably disposed in the vicinity of the front cover at a cassette unloading time;
wherein a second door for closing the cassette insertion opening is slidably disposed in a direction perpendicular to an insertion-unloading direction of the cassette at a loading time of the cassette;
an extension is formed in a portion of the swing cam, and extends in a diametrical direction to a state in which an attachment portion of the swing cam is fixed to a center on the loading base;
a lever has a groove portion in an end tip portion thereof, and this groove portion is engaged with a round projection portion formed on at least one of the right and left sides of the second door;
this lever also has a shaft on a side opposite to this end tip portion, and this shaft extends in the same shaft direction as the attachment portion of the swing cam;
this lever is rotatably attached to a hole formed on at least one of the right and left side surfaces of the base plate so that the lever is moved in association with vertical movement of the second door;
a first cam portion, a notch portion and a second cam portion are formed in the lever;
the end tip portion of the lever is in a position to fully open the second door;
the first cam portion comes into contact with the second extension of the swing cam in a position corresponding to a time when the cassette holder is in a position that provides a cartridge unloading condition;
the first cam portion is formed by a recess portion formed in the shape of an arc with a length like a radius from the attaching portion to the extension, the attaching portion being a center;
an end tip portion of the lever is in a position to fully close the second door;
the notch portion is fitted in the extension of the swing cam in a position corresponding to a time when the cassette holder is in a position that provides a state of loading of the cassette; and
the second cam portion contacts the extension from a fully open state of the second door to a closed state of the cassette insertion opening when the lever is rotated.

In accordance with a tenth construction of the present invention, that: a constricting portion is formed in a lever such that a width of this lever partially in about a central portion thereof Direction as a direction of rotation of the lever is restricted.

In accordance with an eleventh construction of the present invention, that: an evasion section for evading a portion of an attachment member that protrudes into the base plate is formed in the lever when a Cover member for covering an outside of the loading base part on the base plate is attached by a fastener.

In accordance with a twelfth construction of the present invention, the above object is achieved by the following:
a cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that receives a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at a stirring or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base and
a base plate for carrying or holding the loading base part;
wherein the cassette loading mechanism is constructed such that a portion of the loading base for attaching the swing cam thereon is fixed to a tongue portion which is separate from another bent portion.

In accordance with a thirteenth construction of the present invention:
a pin is in an attachment position of the loading base for attaching the swing cam thereon; and
the swing cam is rotatably attached to the loading base by fitting this pin into a hole formed in the swing cam.

In accordance with a fourteenth construction of the present invention, the object can be achieved by:
a cassette loading mechanism with:
a loading base;
a cassette holder for attaching a cassette that stores a loading medium therein;
a carrier for guiding the cassette holder into a predetermined position at the time of inserting or ejecting the cassette;
a base plate for carrying or holding the loading base part;
a first door that freely rotates to open and close a cassette insertion opening and that closes the cassette insertion opening at a time when the cassette is removed or unloaded; and
a second door slidably attached to the cassette loading mechanism in a direction perpendicular to a cassette insertion / unloading direction so that the cassette insertion opening is closed at a time when the cassette is loaded . becomes;
wherein the cassette loading mechanism is constructed such that a rotating shaft is arranged as a center of rotation in each of the right and left lower outer sides of the first door;
a bearing portion for supporting or holding the rotary shaft is arranged on an underside of the cassette insertion opening;
biasing means for biasing the first door on one side of the cartridge insertion opening to which the cartridge loading mechanism is attached; and
the first door is turned down at the cassette insertion time.

In accordance with a fifteenth construction of the present invention applies that: the bearing section detachably on a body of the cassette loading mechanism can be attached and by a material with a high Sliding property is formed.

Further advantages of the present invention will become apparent from the following description and the preferred embodiments of the present invention, as explained in the accompanying drawings. Characteristics of different Embodiments can be combined with one another. Further on with Priority Japanese Application No. 97808/95 (filed March 30, 1995) and No. 256464/95 (filed March 3, 1995). October 1995) on which this application is based, and they will hereby expressly included in the disclosure.

Fig. 1 is an exploded perspective view of a magneto-optical disk drive unit which includes a cassette loading mechanism in accordance with the first embodiment of the present invention;

Fig. 2 is an exploded perspective view showing an internal structure of the cassette loading mechanism of the first embodiment of the present invention;

Fig. 3 is a perspective view showing the appearance of a 130 mm (5.25 inch) type magneto-optical disk;

Fig. 4 is a partially broken perspective view showing the appearance of a cartridge in which the optical disk of Fig. 3 is loaded;
both Fig. 5a and 5b is a plan view showing the constructions of a right lever and a trap;
both Fig. 6a and 6b is an explanatory view showing a makeshift ejection mechanism in accordance with the first embodiment of the present invention;

Fig. 7 is an explanatory view showing the operations of a swing cam and a cassette holder;
. in Figures 8a, 8b and 8c is explanatory views showing the operation or operation of a lever and the opening and closing operations of a second door that are caused by this lever operation;

Fig. 9 is an explanatory view showing rotation of an eject cam and the preload of this eject cam with respect to a bracket;

Fig. 10 is an explanatory view showing an operation of the makeshift ejection mechanism;
. in Figures 11a and 11b is construction views guide form a makeshift ejection mechanism in accordance with the second one of the invention;

Fig. 12 is a side view showing the construction of a mechanical portion near a first door in the first embodiment of the present invention;

Fig. 13 is a side view showing the construction of a mechanical portion near a first door in accordance with a third embodiment of the present invention;

Fig. 14 is a perspective view showing the construction of the first door shown in Fig. 13;
., both the Figure 15a and Figure 15b shows a side view of a lever in the construction humor consistent with a fourth embodiment of the present invention;

Fig. 16 is a plan view of a main portion showing the construction of a mechanical portion near a lever according to the first embodiment of the present invention;

Fig. 17 is a side view showing the construction of a lever in accordance with a fifth embodiment of the present invention;

Fig. 18 is a side view showing the construction of a mechanical portion near the lever according to the fifth embodiment of the present invention;

Fig. 19 is a front view showing an example of a general attachment structure for attaching a swing cam to a cartridge holder;

Fig. 20 is a perspective view showing the construction of a loading base in accordance with a sixth embodiment of the present invention;

Fig. 21 is a front view showing an attachment example of the loading base shown in Fig. 20;

Fig. 22 is a side view of the vibration according shows an attaching structure cam way to the loading base part of the first embodiment of the present invention;

Fig. 23 is a side view showing a mounting structure of the swing cam on the loading base in accordance with the seventh embodiment of the present invention;

Fig. 24 is an exploded perspective view showing the construction of a main portion of a cartridge loading mechanism in an eighth embodiment of the present invention;
each of FIGS. 25a to 25d is a side view showing an operation of the cassette loading mechanism according to the eighth embodiment of the invention; and

Fig. 26 is an exploded perspective view showing the structure of a main portion of a cassette loading mechanism according to a ninth embodiment of the present invention.

The preferred embodiments of a cassette loading mechanism according to the The present invention will next be described in detail with reference to FIG attached drawings described.

Fig. 1 is an exploded perspective view of a disk drive unit including a cassette loading mechanism in accordance with the first embodiment of the present invention. Reference numerals 1 , 2 and 3 denote a recording medium such as a magneto-optical disk, a cassette for storing the medium 1 and a base plate, respectively. Reference numerals 4 , 5 and 6 denote a left frame, a right frame and a front cover, respectively. Reference numerals 7 , 8 and 9 denote a rear cover, a front surface and a rear plate, respectively.

The base plate 3 has a C-shape when viewed approximately from a front side. Upstanding sections 3 a, 3 a, which are bent in a vertical direction, are formed on both side sections of the base plate 3 . Column-shaped sections 3 b, 3 b extend from both ends of each of the upstanding sections 3 a. A small protrusion is formed on a portion of each of the upstanding portions 3 a. A hole 3 c is formed on an area of this small protrusion. Furthermore, an opening section 3 d is formed in a central section of the base plate 3 . Reference pins 3 e for positioning the height of a cassette 2 and the front, back, right and left positions of the cassette 3 are attached to the peripheral portions around this opening portion 3 d.

The left frame 4 and the right frame 5 are each arranged parallel to one another there, namely on the left side and right side of the base plate 3 . The front surface 8 is attached to the front of the base plate 3 . The rear plate 9 is attached to a rear side of the base plate 3 . Thus, a frame body of the cassette loading mechanism is formed. Notch sections 4 a and 5 a are formed in the left frame 4 and in the right frame 5 . A vibration-resistant or a vibration-impermeable rubber 10 is fitted into each of the notch sections 4 a and 5 a. The base plate 3 is attached to this vibration-resistant rubber 10 . The front cover 6 is attached to the front surface 8 of the base plate 3 . The rear cover 7 is attached to the back of the base plate 3 . Thus, a vibration-resistant construction system is formed with respect to the base plate 3 .

A main base plate 11 holds a control unit, etc. Reference numerals 12 , 13 , 14 and 15 denote a chassis, a spindle motor, an actuating device and an optical head, respectively. The spindle motor 13 rotates a recording medium 1 . The actuator 14 is used to input and output recording / reproduction / regeneration signals from data of the recording medium. The spindle motor 13 , the actuator 14 and the optical head 15 are attached to the chassis 12 . The optical head 15 is arranged after the chassis 12 . A head drive base plate 16 is attached to the upper side of the optical head 15 . The main base plate 11 is attached to a lower surface side of the chassis 12 . Furthermore, the chassis 12 is attached to a lower side of the base plate 3 . The spindle motor 13 , the actuating device 14 , etc. are exposed from the opening section 3 d of the base plate 3 or exposed with respect to the opening section 3 d of the base plate 3 .

A loading mechanism, which will be described later, is arranged on the upper side of the base plate 3 . A dust cover 17 is closely attached to the front cover 6 , the rear cover 7 and the base plate 3 from the upper side of the loading unit M. At this time, the opening portion 3 d of the base plate 3 is closed by the chassis 12 , and the lower surface side of the chassis 12 is closed by the main base plate 11 . Therefore, an inside of the base plate 3 forms a perfectly sealing shell structure.

A cassette insertion opening 8 a, an ejection button 8 b and a small hole 8 c for makeshift ejection are formed on the front surface 8 . If the eject button is printed 8 b, an eject switch 39 which is on the main base plate 11 is mounted, turned on or actuated.

Reference numeral 18 denotes a loading base. Various types of structural members that serve to form the loading unit M are assembled or assembled in the loading base 18 . In Fig. 1, reference numerals 19 , 20 and 21 denote a magnetic head, a torsion spring and a lever, respectively. As shown in FIGS. 8a to 8c, this lever 21 is formed by an approximately L-shaped member with long and short extension sections.

A shaft 21 a of the lever 21 is formed vertically near a boundary of these long and short extension portions. A recess portion 21 e is continuously and successively formed by a cam portion A21b, a cam portion B21c and a cam portion 21 d in a central area of the long extension portion. This cam portion A21b is formed in the shape of an arc having a radius r 1 from a first shaft 24 a, which is a center of a later-described rocking cam 24 to an end tip of a projection 24 d. The cam section B21c is formed such that this cam section B21c has a strong inclination compared to the cam section A21b. A base of the cam portion B21c that comes into contact with the end tip of the protrusion 24 d is formed by the notch portion 21 d. Further, a groove portion 21 f is formed in an end tip portion of the long extension portion. Such a lever 21 is biased by a torsion spring 20 at any time in a direction in which the groove portion 21 f is raised.

As shown in Fig. 1, the base plate 3 is arranged as a base, the deepest link in the cassette loading mechanism of the first embodiment. The shaft 21 a of the lever 21 is inserted into the hole 3 c, which is formed in each of the upstanding portions 3 a of the base plate 3 , from the inside thereof, so that the lever 21 is rotatably attached to the base plate 3 .

The front cover 6 is attached to the front of the base plate 3 . The cassette insertion opening 6 b is formed on this front cover 6 . A first door 6 c for opening and closing the cartridge insertion opening 6 b rotatably mounted b at a rear side of the cassette insertion opening. 6 As shown in Figs. 8a to 8c, a second door 6 d is attached to a back of the front cover so that the second door 6 d can slide up and down. A round protruding portion 6 e is formed on each of the two left and right sides of the second door 6 d on its back. The round projection portion 6 e is fitted into the groove portion 21 f of the lever 21 . In the small hole 6 f, which is shown in Fig. 1, it is a through hole of the front cover 6 , which is formed in a portion which is opposite a small hole 8 c.

As mentioned above, the column portion 3 b is formed in each of the four corners of the base plate 3 . The column section 3 b is connected to the loading base part 18 , which is arranged on an upper side of the base plate 3 . Thus, a skeleton of the cassette loading mechanism is formed by the base 3 and the loading base 18 . In this case, it is sufficient to form the column section 3 b in each of the at least three positions.

Fig. 3 is a perspective view showing the appearance of a 130 mm (5.25 inch) type magneto-optic disk. Fig. 4 is a partially broken perspective view showing the appearance of a cartridge in which the optical disc of Fig. 3 is loaded. An access window 2 d is formed approximately on each of the two central surfaces of a cassette 2 . A shutter 2 b for opening and closing the access window 2 d is slidably attached to a cassette body housing 2 a in a shape or form in which the shutter 2 b is rotated upward with an end tip of the cassette as a center or is pivoted. A biasing force for releasing the shutter 2 b is applied to the cassette end tip side of this shutter 2 b. A slot 2 c for a lock opener is formed. The closure 2 b is biased at any time in a closing direction of the access window 2 d. The recording medium 1 is stored in the cassette 2 . A bushing 1 a and a central hole 1 b are formed in the central portion of the cartridge 2 .

In the case of the magneto-optical disk cartridge 2 of the 133 mm type (5.25 inch type), both surfaces of the disk can be accessed so that the above socket 1 a is attached to each of the two cartridge surfaces. In contrast to this, in the case of the magneto-optical disk cartridge of the 90 mm type (3.5 inch type), only one surface of the disk or disk is accessed, so that the socket 1 a is attached to only one cassette surface.

The cassette loading mechanism will next be described with reference to FIGS. 1 and 2.

Fig. 2 is an exploded perspective view showing the construction of the cassette loading mechanism in the first embodiment of the present invention. A cassette holder 22 holds the cassette 2 . A carrier 23 reciprocates a cassette holder 22 . An oscillating cam 24 connects the carrier 23 to the loading base part 18 .

An upstanding portion 18 a is formed on both the left and right of the loading base 18 by bending the loading base 18 in a vertical direction. The upstanding portion 18 a is approximately in a U-shape, as seen from the front of the cassette loading mechanism. A hole 18 b is formed in the upstanding section 18 a. The swing cam 24 is rotatably mounted on the loading base 18 , namely by fitting a first shaft 24 a into the hole 18 b. The first shaft 24 a is mounted vertically on a surface of the swing cam 24 . A second shaft 24 b and a third shaft 24 c are formed on a surface of the oscillating cam 24 opposite their one surface, on which the first shaft 24 a is formed vertically. Axes of three shafts 24 a, 24 b and 24 c are parallel to each other and are located in different places. An extension 24 d extends from the swing cam 24 in a radial direction of the first shaft 24 a.

As shown in Fig. 2, the cartridge holder 22 is formed in a box C-shaped from the front of the cartridge loading mechanism so that a central portion of the cartridge holder 22 is opened on its lower surface. The cassette holder 22 holds the cassette 2 there. Holes 22 b are formed in right and left curved portions 22 a of the cassette holder 22 to hold the cassette 2 there. The second shaft 24 b of the swing cam 24 is fitted into each of the holes 22 b. A sheet-groove 22 c 22 formed on a planar surface of the cartridge holding means on each of its two sides with respect to a central line of the cassette holding means. An opening portion 22d is formed approximately in a central portion of the cassette holder 22 on its upper surface. A claw portion 22 e extends from each portion of the edge portions of the opening portion 22 d.

Two levers consisting of a left lever 25 and a right lever 26 are rotatably attached to this cassette holder 22 . These two levers 25 and 26 are biased at all times in an unloading direction of the cassette 2 . A torsion coil spring or a tension coil spring, etc. are used as a biasing means of the cassette 2 .

Each of FIGS. 5a and 5b is a plan view showing the construction of the right lever 26 . A rotating shaft 27 rotatably supports an end portion of the right lever 26 . A reference numeral 28 denotes a roll. A claw portion 26 a is formed in a central portion of the right lever 26 . A reference numeral 26 b denotes a catcher. This catcher 26 b is formed by an inlet portion 26 c and a groove portion 26 d. The inlet portion 26 c is formed by notching a portion between the claw portion 26 a and the rotary shaft 27 on a rear side surface of the right lever 26 with respect to the cartridge 2 . The groove portion 26 d is connected to the inlet portion 26 c and is formed in the direction of a center line of the right lever 26 on a plane thereof. An L-shaped notch is formed in the right lever 26 through this inlet portion 26 c and the groove portion 26 d. The roller 28 is rotatably attached to another end portion on both the left lever 25 and the right lever 26 . The claw portion 26 a, which is formed in both the left lever 25 and in the right lever 26 , is fitted into each of the arc grooves 22 c, 22 c (see FIG. 2), which are formed in the cassette holder 22 are so that the positions of the left lever 25 and the right lever 26 are restricted in their directions of rotation.

When the cassette 2 is inserted into the above cassette holder 22 in a state that a B surface of the cassette 2 is facing up, the roller 28 at the end tip of the right lever 26 is inserted into the slot 2 c for one Lock opener (see Fig. 4) as shown in Fig. 5a. When the cassette holder 22 is pushed further, the right lever 26 rotates as shown in Fig. 5b in a state in which the roller 28 is fitted in the slot 2 c for a shutter opener (see Fig. 4) . Thus, the shutter 2 b (see Fig. 4) of the cassette 2 is opened. When the cassette 2 is inserted into the cassette holder 22 in a state in which an A surface of the cassette 2 is upward, the shutter 2 b (see FIG. 4) is opened by the left lever 25 .

In Fig. 2, the carrier 23 is formed by a plate-shaped member which is approximately in the form of a rest base and has a central opening portion 23 a. An upstanding portion 23 b is formed in the bracket 23 by bending this bracket 23 on both its left and right sides. The hole 23 c is formed in the upstanding portion 23 b. The third shaft 24 c of the swing cam 24 is fitted in this hole 23 c. A hole 23 d for attaching a carrier spring 29 is formed at each of the edges of the opening portion 23 a on a front of the carrier 23 . The carrier 23 is biased by this carrier spring 29 at any time in an insertion direction of the cassette 2 .

A pin 23 f for receiving an end tip of an ejection lever 33 , which will be described later, is attached to an extension portion 23 e of the bracket 23 in a front central portion thereof. A roller 30 is formed on an extension portion 23 g which is formed in a rear portion of the carrier 23 . A notch 23 has approximately an L-shape and is formed on a plane of the support 23 in a lying at the right side, rear portion thereof h. As shown in FIGS . 5a and 5b, this notch section 23 h is formed by a vertical section 23 i, a rectilinear section 23 j and by an inclined section 23 k. The vertical section 23 i extends in a vertical direction perpendicular to a cassette insertion / unloading direction. The straight section 23 j is connected to the vertical section 23 i and extends in the cassette unloading direction. The inclined portion 23 k is formed in a boundary portion of the vertical portion 23 i and the straight portion 23 j.

A catch 31 holds a position of the carrier 23 with respect to the loading base 18 when the cartridge is unloaded. As shown in Fig. 5a and 5b, this trap or latch is a pin 31 c, a roller 32 and a hole portion 31 f formed by an approximately 31 F-shaped plate 31 a Trap. The pin 31 c is vertically attached to an end portion of an extension piece 31 b, which is formed in a central portion of this trap plate 31 a. The roller 32 is attached to an end portion of a horizontally extending piece 31 d. The hole section 31 f is formed in another end section of the horizontally extending piece 31 d, from which an extension piece 31 e extends.

The case or latch 31 is rotatably supported with respect to the loading base part 18 by the pin c 18, which is attached to the loading base part 18, f in the hole portion 31 as shown in Fig. 2, is fitted. , As shown in Figures 5a and 5b, the position of the carrier 23 by the roller 32 h in the notch 23 is further. Shown held with respect to the loading base part 18 to the loading time of the cassette (latched or snap-fitted) of the carrier 23 is fitted. The trap 31 is biased in a counterclockwise direction as viewed from above.

In Fig. 6a and 6b, a makeshift eject button 34 is rotatably connected to one end of an eject lever 33. A central portion of the eject lever 33 is rotatably supported by the loading base 18 . The other end of the ejection lever 33 is located behind the pin 23 f (see FIG. 2) of the carrier 23 . A rod or bolt contact section 34 a provided with a depression is formed in an end tip of this makeshift ejection button 34 . This rod or bolt contact portion 34 a receives an end tip of a rod or bolt (described later) as an actuator that is inserted into the drive unit at a makeshift ejection time or an emergency ejection time. A hole 33 a is formed approximately in the central portion of the eject lever 33 . A pin 18 d of the loading base 18 is fitted into this hole 33 a and is locked or held by an E-ring 35 , so that the eject lever 33 is rotatably held by the loading base 18 .

In Fig. 2, an ejection unit 36 consists of a mechanism to move the carrier 23 up and down. This ejection unit 36 is formed by a base plate 36 a, an ejection motor 36 b, a reduction gear train 36 c, an ejection cam 36 d, etc. The ejection motor 36 b and the reduction gear train 36 c are formed on the base plate 36 a. The ejection cam 36 d is formed at an output stage of this reduction gear train 36 c. The ejection unit 36 is fastened to the loading base part 18 in at least two positions.

As shown in Fig. 2, the magnetic head 19 has a coil 19 a for applying a bias field to the recording medium 1 . A pin 19 b is attached to each of the right and left sides of the magnetic head 19 . The pin 19 b is fitted into a hole 37 a, which is formed in a magnetic head holder 37 so that the magnetic head 19 is rotatably attached to the magnetic head holder 37 .

A U-shaped groove 37 b is formed at each of the rear ends of the magnetic head holder 37 . A shaft 18 f is formed in each of the edge portions of an opening portion 18 e, which is formed in a central portion of the loading base 18 . The magnetic head holding device 37 is rotatably attached to the loading base 18 by the groove 37 b is attached or adapted to the shaft 18 f. The magnetic head holder 37 is biased by a torsion coil spring 38 at all times in a downward direction, that is, a loading direction of the cassette. A protruding portion 37 c protrudes on a lower side of the magnetic head holder 37 .

A central screw portion of the torsion coil spring 38 is fitted on the above shaft 18 f. One end of the torsion coil spring 38 comes into contact with the magnetic head holder 37 . The other end of the torsion coil spring 38 comes into contact with the loading base 18 . Thus, the torsion coil spring 38 is attached to the magnetic head holder. At this time, it is sufficient to form the torsion coil spring 38 as well as the shaft 18 f, the groove 37 b and the protruding portion 37 c of the magnetic head holding device 37 in at least one position. A train screw spring can also be used as a pretensioner at this time. In this case, it is necessary to install the bias coil spring in a direction approximately parallel to its vertical direction of the cassette holder 22 .

Operation of the cassette loading device in the first embodiment as one Time at which the cassette is inserted will be described next.

As shown in Fig. 7, when the cassette 2 is inserted into a cassette insertion opening 8 a formed on the front surface 8 in the direction of an arrow A, the cassette 2 is inserted into the cassette holder 22 , while the first door 6 c of the front cover 6 is pushed through the cassette 2 and opened. Thus, as shown in FIGS. 5a and 5b, the roller 28 at an end tip of the right lever 26 or the left lever 25 (in FIGS. 5a and 5b the right lever 26 ) is inserted into the slot 2 c for a locking device. Cassette 2 opener fitted. When the cassette 2 is pushed further, the right lever 26 starts to be rotated in the direction of the arrow B. Accordingly, the shutter 2 d is gradually opened in the direction of an arrow C (shown in Fig. 5a).

The pin 31 c of the trap 31 passes through the inlet portion 26 c of the catcher 26 b, which is formed by an L-shaped notch which is formed in the right lever 26 . Then the pin 31 c comes into contact with a wall of the catcher 26 b, ie a side surface of the groove section 26 d. The case 31 is biased by this time to c by the pin 31 of the right lever 26th Therefore, the trap 31 starts to be rotated in the direction of an arrow D. Thus, the roller 32 , which is in a falling state with respect to the vertical portion 23 i of the carrier 23, is rotated on the notch 23 h.

When the latch 31 begins to be rotated, the roller 32 also begins to be rotated. When the roller 32 is then rotated to a position which goes k over an edge 23L of the vertical portion 23 i and the inclined portion 23, the Trap or snap-in state of the roller 32 and the vertical portion 23 is achieved i. Thus, no restraining force with respect to biasing the beam 23 in the A direction is applied to the beam 23 at any time, so that the beam 23 starts to be moved in the A direction. The roller 32 is pushed through the inclined portion 23 k immediately after this movement of the carrier 23 . Therefore, the catcher 26 b is rotated further so that the pin 31 c begins to be moved to a lower portion of the groove portion 26 d of the catcher 26 b. At this time, the carrier 23 is further moved in the A direction by the inclined portion 23 k of the notch 23 h being moved by the roller 32 . When the roller 32 is moved to the straight portion 23 j of the notch 23 h, the roller 32 engages with an end portion of the notch 23 h as shown in Fig. 5b. The latch or snap pawl 31 is thus held or locked against the pretensioning of the carrier springs 29 (see FIG. 2).

Since the pin 31 c is simultaneously fitted into the groove portion 26 d of the catcher 26 b, no right lever 26 is returned in a biasing direction, so that the rotation of the right lever 26 is stopped. The right lever 26 is namely clamped or clamped. The claw portion 26 e is formed at an end tip of the right lever 26 . An end tip of the left lever 25 is pressed by this claw portion 26 e, so that the rotation of the left lever 25 is also stopped.

Further, as shown in Fig. 2, the third shaft 24 c of the swing cam 24 is fitted in the hole 23 c of the carrier 23 . The first shaft 24 a of the swing cam 24 is fitted into the hole 18 b of the loading base 18 . Therefore, as shown in FIG. 7, when the carrier 23 starts to be moved in the direction of the cartridge insertion (in the A direction), the swing cam 24 starts to be rotated in the direction of an arrow E. The second shaft 24 b of the swing cam 24 is fitted in the hole 22 b of the cassette holder 22 . Therefore, the cassette holder is lowered in a state 22 in which the cassette is loaded into the cartridge holder 22 22nd

When the cassette 2 is loaded in the cassette holder 22 , the shutter 2 b (see FIG. 4) is fully opened by the right lever 26 (see FIG. 2) or by the left lever 25 (see FIG. 2). Therefore, the socket or hub 1 a (see FIG. 3) is exposed by the access window 2 d (see FIG. 4). When the cassette holder 22 is lowered, the bushing 1 a (see FIG. 4) engages with an end tip of the spindle motor 13 so that the recording medium 1 (see FIG. 4) is clamped by the spindle motor 13 or clamped.

When the cassette holder 22 has been completely lowered, the cassette 2 is close to the reference pin 3 e (see Fig. 1) and is positioned.

In FIG. 2, the protruding portion 37 reaches c, the direction in which the magnetic head Halteein 37 is formed in contact with an upper surface of the cassette holder 22, so that the magnetic head 19 which is attached to the loading base part 18, is located above the cassette holder 22 . However, when the cassette holder 22 is lowered by releasing the latch, the magnetic head 19 is also lowered due to the bias of the torsion coil spring 38 . When the magnetic head 19 is lowered, a lower surface of the magnetic head 19 comes into contact with the claw portion 22 e of the cassette holder 22 . When the magnetic head 19 is further lowered, the magnetic head 19 comes into close contact with the claw portion 22 e. The magnetic head 19 is thus positioned in its height direction.

Each of FIGS. 8a to 8c is an exemplary view showing positions of the lever 21 and the swing cam 24 in a cassette unloading state when the latch is released.

As shown in Fig. 8a, the extension reaches 24 d of the swing cam 24 in contact with the cam portion A21b of the lever 21, up to a release or solution at the time of the event. Therefore, the groove portion 21 f is held or locked at an end tip of the lever 21 in a lowest or lowest position. The second door 6 d is also in its lowest position. The second door 6 d is namely in a state in which the cassette insertion opening 6 b is fully open.

In this state, when the latch 31 (see Fig. 5a) is released and the swing cam 24 starts to be rotated, an end tip of the extension 24 d gradually becomes toward the cam portion B21c of FIG moved from the cam portion A21b. When the swing cam 24 is rotated about 2/3 of its total rotation angle, the extension 24 d is disengaged from the cam portion A21b, as shown in Fig. 8b, so that the extension 24 d in a portion of the cam portion B21c is moved. At this time, the lever 21 is biased at all times in a direction in which an end tip portion of the lever 21 is raised. Accordingly, the lever 21 starts to be raised and the second door 6 d also starts to be raised. At this time, the cassette 2 is already gradually lowered by approximately 2/3 of an entire loading stroke. Therefore, when the cassette 2 has been completely lowered, the extension 24 d is engaged with the notch portion 21 d so that the rotation of the swing cam 24 is stopped.

At this time, the extension 24 d is rotated up to a portion of the notch portion 21 d through the portion of the cam portion B21c, as shown in Fig. 8c. Accordingly, the lever 21 is raised completely, so that the cassette insertion opening 6 b is completely closed by the second door 6 d.

The loading operation of the cassette was in accordance with the above procedures accomplished.

Ejection operation of the cassette will be described next.

In Fig. 1, the eject switch 39 is turned on by pressing the eject button 8 b by an operator. Thus, commands to start the ejection motor 36 b (see FIG. 2) are issued from the main base plate 11 , so that the ejection motor 36 b (see FIG. 2) begins to rotate. As shown in FIG. 9, the ejection cam 36 d starts rotating in the direction of an arrow F. Then the ejection cam 36 d pushes the roller 30 of the carrier 23 . Thus, the carrier 23 is moved in an unloading direction (the direction of an arrow A ') of the cartridge against the biasing force of the carrier springs 29 (see Fig. 2). In this case, as shown in Fig. 7, the swing cam 24 begins to rotate in a direction opposite to a loading direction, that is, in the direction of an arrow E ', so that it starts that Cassette holder 22 is raised. Correspondingly, the cassette 2 begins to be raised.

When it starts, the swing cam 24 is further rotated, the extension 24 passes d in contact with the cam portion B21c, as shown in Fig. 8c. It also begins that the extension 24 d pushes the lever 21 . When the cam portion B21c is pushed, torque is applied to the lever 21 in a direction opposite to the biasing force of the torsion spring 20 . Therefore, it starts that the lever 21 is rotated in this opposite direction, that is, to a lower side. As a result, as shown in Fig. 8b, it begins that the second door 6 d is lowered so that the opening of the cassette inlet opening 5 b begins.

If the oscillating cam 24 is rotated further, the extension 24 d is moved into the region of the cam section A21b, as shown in FIG. 8a. At this time, the swing cam 24 has been rotated to a position in which the lever 21 is completely lowered. Similarly, the second door 6 d is opened so that the cassette inlet opening 6 b is fully opened.

At this time, the swing cam 24 is moved along a path which is the reverse of that in the loading time of the cassette. Accordingly, the swing cam 24 is rotated back only about 1/3 of its full rotation angle. Accordingly, the cassette holder 22 is also raised by only about 1/3 of its full stroke. However, an inner surface of the cassette 2 lifts a deeper surface of the recording medium 1 when the cassette holder 22 is raised to a certain extent so that the jamming of the hub 1 a (see Figs. 3 and 4 ) and the spindle motor 13 (see Fig. 1) is solved.

With respect to an upper portion of the cartridge holding means 22 shown in Fig. 2, the magnetic head 19 is slid by the claw portions 22 e and lifted when the cassette holding means 22 is raised. When the magnetic head 19 is raised to a certain extent, the protruding portion 37 c of the magnetic head holder comes into contact with an upper surface of the cartridge holder 22 . When the magnetic head 19 is further raised, the magnetic head 19 comes into contact with the upper surface of the cassette holder 22 . If the magnetic head 19 is raised further, the cassette holder 22 pushes the projecting portion 37 c, so that the magnetic head 19 is raised by the cassette holder 22 .

When the eject cam 36 d further resistant to the carrier 23 moves, a contact portion of the notch portion 23 is h, which comes into contact with the roller 32 of the case 31, from the straight portion 23 j k to the inclined portion 23 as shown in Figure . 5a and 5b, moved, so that the edge 23 is moved to a position l of the roller 32. At this time, the cassette 22 is raised to about the height of an unloading position. When the edge 23 l passes beyond the position of the roller 32 , the roller 32 is moved into the vertical portion 23 i by the biasing force applied to the latch 31 so that the latch 31 immediately begins to be rotated.

When the turning of the trap 31 begins, an engaged state between the groove portion 26 d of the catcher 26 b and the pin 31 c of the trap 31 is released . Accordingly, the right lever 26 starts to immediately turn with the biasing force applied to the right lever 26 . Similarly, the left lever 25 starts rotating immediately since an engagement state between the left lever 25 and the claw portion 26 e of the right lever 26 is released. As a result, the cassette 2 is pushed out, so that the cassette 2 is discharged from the cassette insertion opening 6 b (see Fig. 1) in the direction of arrow A '.

Shortly after the cassette 2 has been unloaded, the ejection cam 36 d (see FIG. 2) pushes a stop switch, not shown. Thus, commands to stop the operation of the ejection motor 36b (see FIG. 2) are issued to the main base plate 11 (see FIG. 1). Accordingly, the rotation of the ejection motor 36 b (see Fig. 2) is stopped, so that the ejection operation of the cassette is completed.

A makeshift ejection function of the cassette loading mechanism will now be described with reference to FIGS. 6 and 10.

If there is a break in the electrical power supply etc. in one If the cassette is in a loaded state, the ejection motor cannot be turned.  

Accordingly, it is necessary to use a makeshift ejection function for the cassette To provide loading mechanism.

As shown in Fig. 10, a rod 40 such as a piano wire or a screwdriver with a thin end, etc. is inserted into the small hole 8 c formed on the front surface 8 for temporary ejection to perform the operation. At this time, the small hole 6 f is formed similarly in the front cover 6 . Accordingly, the rod 40 is inserted into the interior of the drive unit. When the rod 40 is inserted further, reaches an end-tip of the rod 40 into contact with a rod contact portion 34a of the eject button makeshift 34th When the rod 40 is pushed further, the eject lever 33 is rotated. Thus, an end tip of the eject lever 33 is moved in the cassette discharge direction (unloading direction), so that this end tip of the eject lever 33 pushes the pin 23 f of the carrier 23 . A subsequent operation is similar to that in explaining the cartridge ejection operation. Therefore, this operation is omitted in the following description. The eject lever 33 is normally biased clockwise in FIG. 10 by a torsion spring 41 . Accordingly, no end tip of the eject lever 33 comes into contact with the pin 23 f, so that no loading and ejecting operations of the cassette are prevented by the eject lever 33 .

In accordance with the above first embodiment, the carrier 23 is placed in the cassette loading mechanism on an upper side of the cassette holder 22 . Accordingly, it is possible to free a space that is generally occupied by the carrier on a lower side of the cassette holding device 22 . Therefore, a dustproof structure can be provided as a perfectly sealing structure. Furthermore, it is possible to solve a general technical problem, after which it is difficult to thin the drive unit.

The carrier 23 is arranged on the upper side of the cassette holder 22 so that it can be seen that no space is used for the upper side. However, only the magnetic head 19 is arranged on the upper side of the cassette holder 22 . Therefore, there is no construction element outside the magnetic head 19 . Accordingly, a space for the cassette loading mechanism can be used more effectively in the first embodiment.

The above explanation relates to the first embodiment. The first embodiment uses a mechanism to move the cassette holder 22 through the swing cam 24 from top to bottom. Therefore, the beam 23 is biased in a direction opposite to that of the general or known technique. The carrier 23 is namely biased in the direction of insertion of the cassette when the cassette is loaded. Accordingly, the carrier 23 must be biased in the unloading direction of the cassette to perform the makeshift ejection operation, so that the eject lever 33 is required. Therefore, the number of parts of the cassette loading mechanism is increased, and a retainer such as an E-ring, etc. is required, so that the number of assembly operations is increased.

Furthermore, in the first embodiment, the eject lever 33 must be pushed from outside the drive unit at the temporary unloading time of the cassette. However, no push portion of the eject lever 33 may be exposed to the outside of the drive unit with respect to the makeshift discharge. Therefore, the small hole 8 c is formed on the front surface 8 . The unloading operation is passed through by the rod 40, such as a piano wire, a screwdriver with a thin end, etc. is introduced c in this small hole 8 and by the internal ejection lever is pressed 33rd At this time, it is desirable to mount 34 at a tip end of the eject lever 33 to makeshift eject button or so that the rod 40 which is inserted from the outside, can reliably press the end tip of the makeshift lever 33 to be mounted. However, the number of parts of the cassette loading mechanism is increased in this case, so that there is a problem of an increase in the number of operations. Further, as shown in Fig. 6b, a clearance for moving the makeshift eject button 34 in a vertical direction (H direction) must be secured with play. Therefore, no magneto-optical disk unit can be made thinner. Further, a vertical position of the makeshift eject button 34 becomes less accurate due to this margin. Therefore, there is a case after the rod 40 is inserted into the small hole in which no end tip of the rod 40 is positioned exactly at the end tip of the makeshift eject button 34 , so that the operability of the rod 40 is reduced .

The following second embodiment of the present invention solves such a problem. Each of FIGS. 11a and 11b is a perspective view showing a cassette makeshift mechanism in accordance with the second embodiment of the present invention. In a loading base 50 is an attachment portion 50 a for attaching a makeshift ejection button 51 , which will be described later, in the loading base 18 in the first embodiment and a stepped pin 50 d for attaching an eject lever 52 , which will be described later is vertically attached to the loading base 18 in the first embodiment. This attachment portion 50 a is formed by a notch portion 50 b and a stepped claw portion 50 c as a support portion of an eject button which extends from each of the two sides of this notch portion 50 b. The stepped pin 50 d is constructed by a shaft section 50 e and a head section 50 f which has a diameter which is larger than the shaft section 50 e and which is formed at one end of the shaft section 50 e. The same structural members as in the first embodiment are denoted by the same reference numerals in Figs. 11a and 11b, and their detailed description is omitted in the following description.

Reference numeral 52 denotes an eject lever. A hole 52 a is formed in a central portion of a body of the eject lever 52 . This hole 52 a is formed by a hole section 52 b and an elongated hole section 52 c. The above head portion 50 f can pass through the hole portion 52 b. The elongated hole section 52 c is continuous and integrally formed with this hole section 52 b. The shaft 50 e can be fitted into the elongated hole section 52 c. A step is formed at an end portion of the body of the eject lever 52 . A lever pin 52 d is vertically attached to an end tip portion of this stage of the raising lever 52 . A torsion spring 41 is attached to another end portion of the eject lever 52 .

Reference numeral 51 denotes a makeshift eject button. This makeshift eject button 51 has a sliding groove 51 a, which is formed in the same direction as a pressure direction of the makeshift eject button 34 on each of the two sides of the makeshift eject button 34 according to the first embodiment. The claw portion 50 c is fitted into this sliding groove 51 a. A hole 51 b is formed in an extension portion that extends from a rear surface of the makeshift eject button 51 . A central axis of this hole 51 b is perpendicular to the printing direction of the emergency eject button 51 . An end tip of a rod 40 (see Fig. 10) comes into contact with a rod contact portion 51c.

The eject lever 52 is rotatably attached to the above stepped pin 50 d through the hole 52 a. Next, the lever pin 52 d is inserted into the hole 51 b of the emergency eject button 51 . A biasing direction of the torsion spring 41 is directed approximately in accordance with the direction of an axis, the portion from the center of the hole 52 b from a center of the elongated hole portion 52 c. The biasing direction of the torsion spring 41 is approximately in accordance with a biasing direction of the carrier 23 when the cartridge is loaded.

With such a structure, the eject lever 52 is attached to the loading base 50 only in that the stepped pin 50 d is inserted into the hole portion 52 b. Therefore, it is not necessary to separately perform a fastening operation of a cutting washer or an E-ring stop or an E-ring holding device, etc. Furthermore, it is sufficient to fit the lever pin 52 d into the hole 51 b when the makeshift eject button 51 is attached to the eject lever 52 . Accordingly, it is not necessary to perform the fastening operation such as with a screw stop or an E-ring stop or an E-ring holding device, etc. Therefore, the effects in the first embodiment can be achieved while minimizing an increase in the number of assembly operations. Next, the claw portion 50 c of the loading base 50 is slidably fitted into the sliding groove 51 a, so that a play of the makeshift eject button 51 in a vertical direction only by the play or the free spaces of the sliding groove 51 a and Claw section 50 c is formed. Accordingly, the play of the makeshift eject button 51 in the vertical direction can be reduced, so that inoperability of the rod 40 can be reduced.

There is now a cassette loading mechanism in accordance with a third Embodiment of the present invention described.

In the first embodiment, as shown in FIGS. 2 and 12, the carrier 23 is arranged on the upper side of the cassette holder 22 so that the eject lever 33 and the makeshift eject button 34 are also arranged on the upper side of the cassette holder 22 is. At this time, the makeshift eject button 34 is in a position that is higher than that c of the first door 6, so that (a rod 40 which is inserted into the interior of the drive unit to the Behelfs-discharge time of the cassette is is in a disruptive engagement with the first door 6 c, which is completely open at the unloading time (or the insertion time) of the cassette 2. Therefore, a drive unit with a thin structure or with a thin structure cannot be produced.

Further, in the first embodiment, as shown in Fig. 2, the carrier 23 is arranged on the top of the cassette holder 22 , so that the throwing lever 33 is also arranged on the top of the cassette holder 22 . In this connection, a basket body of the drive unit is divided into two sections, which consists of the loading base part 18 on an upper side and the base plate 3 on an underside. The basket body has a structure in which the carrier 23 , the cassette holder 22 , the swing cam 24 and the eject lever 33 are attached to the loading base 18 on the top. At this time, it is desirable that the charging base 18 and the base 3 be fixed to each other on the top for a dustproof construction. Therefore, the loading base 18 , as shown in Fig. 1, by screws in four corner screw retaining portions 3 f, which are formed in pillar sections 3 b of the base plate 3 , attached. In particular, there is no problem in assembling both the loading base 18 and the base 3 because there is sufficient space in each of the two positions on the rear of the drive unit. However, there is the first door 6 c in two positions on the front of the drive unit. Therefore, it is necessary to arrange the loading base 18 in the height positions of the screw holding portions 3 f so that no drive unit can be made structurally thin.

The following third embodiment of the present invention is made with respect to provided such problems.

Fig. 13 is a side view showing the construction of the cassette loading mechanism near a cassette insertion opening in the third embodiment. FIG. 14 is a perspective view showing the constructions of a front cover and a first door shown in FIG. 13. Numeral 55 denotes a first door in the third embodiment. A protruding portion 55 a is formed in each of the two end portions of the first door 6 c according to the first embodiment. An end tip of the cassette 2 comes into contact with the projecting section 55 a. A recess portion 55 b is on a rear side of the projecting portion 55 a formed. A groove portion 55 c is formed on a rear surface of the first door 6 c according to the first embodiment. The first door 55 is namely constructed in the third embodiment so that the first door 6 c according to the first embodiment has the projecting section 55 a, the recess section 55 b and the groove section 55 c. The same construction members as the first embodiment or construction members having the same function as the first embodiment are denoted by the same reference numerals, and their detailed description is omitted in the following description.

In the third embodiment, a makeshift eject button 34 is disposed behind a free end of the first door 55 when the first door 55 is fully opened. At this time, the groove portion 55 c is formed approximately in parallel with a line connecting a small hole 6 f of the front cover 6 <34516 00070 552 001000280000000200012000285913440500040 0002019639378 00004 34397 / BOL <to a rod contact portion 34a of the makeshift eject button 34 so that this groove portion 55c is located vertically below this line. A screw-holding portion 3f for the charging base 18 is formed in each of the four corners of the base 3. When the first door 55 is fully opened at the time of inserting or unloading the cartridge 2, the recessed portion 55b and the protruding portion 55a are vertically below two front screw retaining portions 3f from the four corner screw retaining portions 3f. As mentioned above, the makeshift eject button 34 is arranged after the first door 55 in the third embodiment. Further, the groove portion 55c is formed on a back surface of the first door 55. Accordingly, the rod 40 inserted into the inside of the drive unit is fitted in this groove portion 55c at a makeshift unloading time of the cartridge. Therefore, the effects in the first embodiment can be obtained without preventing the drive unit from being made thin. When the first door 55 is fully open, a first position of the protruding portion 55a matches the position of a front screw holding portion 3f. Further, the recess portion 55b is formed on the back surface of the protruding portion 55a. Accordingly, an end tip of a screw protruding from the screw holding section 3f and a back of the screw holding section 3f is fitted in the recessed section 55b even if the screw holding section 3f is at the same height position as the first Door 55 is lowered and the first door 55 is fully open at the cassette insertion or unloading time. Therefore, the screw and the first door 55 do not interfere with each other, so that the drive unit can be made thin. A cassette loading mechanism in accordance with the fourth embodiment of the present invention will be explained next. 8a to 8c, a position of the second door 6d when the second door 6d is in an open state is determined by the positional relationship between the second door 6d and the groove portion 21f at the tip end of the lever 21. However, there is variation in the relative positions of the extension 24d and the cam portion A21b. Therefore, there is also a variation in the vertical position of the groove portion 21f. At this time, a second door 6d is not lowered further if a lower end of the second door 6d is located in the same position as an inside of the front cover 6, so that the extension 24d and the cam portion A21b are interfered with each other. Accordingly, the swing cam 24 cannot be rotated so that the cassette 2 cannot be unloaded. Therefore, it is necessary to form a clearance in the amount of the scatter "a" from the inside of the front cover 6 at the lower end of the second door 6d even in the deepest position of the groove portion 21f. This play prevents the drive unit from being made thin. The following fourth embodiment of the present invention is provided to solve such a problem. 15a shows a lever in the fourth embodiment. A constricted portion 21g is formed approximately in the central portion of the lever 21. That is, the lever in the fourth embodiment is provided by forming approximately a constricted portion in a central portion of the lever 21 in the first embodiment. The same structural members as in the first embodiment or structural members each having the same function as in the first embodiment are denoted by the same reference numerals, and their detailed description is omitted in the following description. In such a fourth embodiment, the necked portion 21g is elastically deformed because the necked portion 21g is formed in the lever 21 of the first embodiment even if the nominal position of a lower end of the second door 6d is in the same position as an inside of the front cover 6 is arranged. Accordingly, the constricted portion 21g absorbs scatter in the position of the groove portion 21f. Therefore, it is possible to solve or eliminate the disadvantage that the swing cam 24 cannot be rotated. As shown in Fig. 15b, the above-mentioned effects can also be obtained even if a notch portion 21h is formed such that this notch portion 21h surrounds a peripheral portion of a shaft 21a from an outside of the lever 21. Further, a spring constant can be reduced compared to the lever shown in Fig. 15a. Therefore, it is possible to more reliably solve the problem that the swing cam 24 cannot be rotated. A cassette loading mechanism in accordance with a fifth embodiment of the present invention will now be described. As shown in FIG. 16, the lever 21 is formed just inside a dust cover 17 in each of the left and right directions immediately after the front cover 6. Therefore, a screw-holding portion of the dust cover 17 cannot be formed immediately after the front cover 6. Accordingly, the dust cover 17 and the front cover 6 do not come into close contact with each other in a position near the lever 21, so that the external dust tends to enter the cartridge loading mechanism. The following fifth embodiment of the present invention is also provided to solve such a problem. 17 shows a lever according to the fifth embodiment. An elbow type escape portion 21h is provided by partially forming an approximately central portion of the lever 21 of the first embodiment in an angular shape on an upper surface. The same structural members in the first embodiment or structural members having the same function as in the first embodiment are denoted by the same reference numerals, and their detailed description is omitted in the following description. In such a fifth embodiment, the avoidance portion 21h is formed in the lever 21 as shown in FIG. 18. Therefore, a screw stop portion 17a of the dust cover 17 can be formed in a position corresponding to this evasion portion 21h. Further, when a partial width or a section width of the lever 21 is set in the escape section 21h to be narrowed in comparison with the other sections of the lever 21, this narrow section tends to be elastically deformed, so that effects can be obtained, which are similar to those of the fourth embodiment. A sixth embodiment of the present invention will be explained next. In Japanese Patent Application Laid-Open (KOKAI) No. 3-108154, a swing cam is used as a well-known example of a typical cassette loading mechanism in a magneto-optical disk unit so as to be dustproof in performance by a perfectly sealing structure as in the prior art the technology is described to ensure. According to this example, a stable cassette loading mechanism with a high dust-proofing efficiency can be achieved with a small number of construction parts. However, according to this example, a tray 101 is attached to a basket body 100 after a carrier and a cam 102 are attached to the basket body 100. Therefore, it is necessary to fit the tray 101 (see FIG. 19) into the basket body 100 while the cam 102 is bent outward by the tray 101 (see FIG. 19). Plastic, such as polyacetal resin, etc., is currently used as a material for the cam 102 considering the lubricity. The thickness of this plastic is relatively small. Therefore, the cam 102 is deformed if the curvature of the cam is left as it is at this fitting time. When a fitting amount (protruding amount) of the cam with respect to the tray 101 on an effective axis 102 of the cam is decreased to easily fit the cam into the tray, the amount of engagement of the cam and the tray is reduced. Therefore, the cam is disengaged from the tray during a cassette unloading operation so that no cassette can be accurately loaded and unloaded. The following sixth embodiment of the present invention is provided to solve such a problem. 20 is a perspective view showing the structure of a loading base according to the sixth embodiment. Reference numeral 56 denotes a charging base according to the sixth embodiment. A tongue portion 56a is a bent portion for attaching a swing cam 24 to the loading base 18 according to the first embodiment. A bent portion 56b is formed by bending processing together with the tongue portion 56a and is adjacent to the tongue portion 56a. The tongue section 56a and the bent section 56b are separated from each other into bending processing sections. In such a sixth embodiment, as shown in FIG. 21, only the tongue portion 56a formed in the loading base 56 is bent when a cassette holder 22 is attached to the swing cam 24. Accordingly, unlike the general cassette loading mechanism, it is not necessary to bend the swing cam 24 so that the swing cam 24 is not deformed. Further, a protruding width of a second shaft 24b can be set so that cartridge loading and unloading operations can be performed without any problems. A seventh embodiment of the present invention will next be described. In the first or sixth embodiment, the first shaft 24a formed in the swing cam 24 is inserted into the hole 18b of the loading base. This hole 18b is formed by a press molding in view of the mass production and contents in which the loading base is formed by a sheet such as an iron plate, etc. Therefore, as shown in FIG. 22, portions of the hole 18b are formed by a broken face 60 and a sheared face 61. Accordingly, a side surface of the first shaft 24a first comes into contact only with the shear cutting portion 61 which has a low surface roughness, so that no problems are caused. However, as wear of a wall portion of the hole 18b progresses through repetition of the cartridge loading and unloading operations, the side surface of the first shaft 24a will soon come into contact with the fracture face 60. Accordingly, the amount of wear of the wall portion when a certain time is exceeded will suddenly increase, so that the life of mounting and removing the cassette cannot be extended. The following seventh embodiment of the present invention is provided to solve such a problem. 23 is a view showing the construction of a main portion of a cartridge loading mechanism according to the seventh embodiment. A pin 57 is attached to a portion corresponding to the hole 18b of the loading base 18. A reference numeral 58 denotes a swing cam according to the seventh embodiment. This swing cam 58 has a hole 59 formed in a portion corresponding to a first shaft 24a of the swing cam 24 in the first embodiment. The pin 57 is fitted in this hole 59 so that the swing cam 58 is rotatably attached to the loading base 18. In such a seventh embodiment, the pin 57 is arranged instead of the hole 18b of the loading base part 18 and the hole 59 is formed instead of the first shaft 24a of the oscillating cam 24. Accordingly, the pin 57 is slidably inserted into the hole 59 with a high degree of accuracy or care regarding the surface roughness, so that the wear of the swing cam 24 is not increased from a certain point in time. Thus, the life of the cassette attachment and detachment can be greatly increased. A circumference b by which the pin 57 protrudes on the outside of the loading base 18 is at most approximately 0.2 mm and can be reduced in comparison with the circumference by which the first shaft 24a protrudes. Accordingly, the drive unit can be made compact in terms of its width direction. An eighth embodiment of the present invention will next be described. 24 is an exploded perspective view showing a main portion of a cartridge loading mechanism according to the eighth embodiment. A surface member 110 has a cartridge insertion opening 110a on the front surface of the cartridge loading mechanism. A second door 111 is formed up and down on a rear portion of the sheet 110 to open and close the cassette insertion opening 110a. A first door 112 is rotated in the back portion of the sheet 110 to open and close the cassette insertion opening 110a. A front cover 113 having a frame shape rotatably supports the first door 112. A torsion spring 114 biases the first door 112 on one side of the cartridge insertion opening 110a at all times. A lever 115 moves the second door 111 up and down. In Fig. 24, the same members as in the first embodiment shown in Fig. 1 are given the same reference numerals, and a detailed description of these members is omitted in the following description. This eighth embodiment relates to a peripheral structure of the cartridge insertion opening on a front side of the cartridge loading mechanism of the first embodiment. As shown in FIG. 24, an extension portion 111a extends in a vertical direction to both ends of the second door 111. A round protrusion 111b is formed vertically on a surface of the extension portion 111a parallel to the longitudinal direction of the second door 111. The second door 111 has the same basic construction as the second door 6 according to the first embodiment, but the round protrusion 111b is in a position higher than that of the round protrusion 6e (see Fig. 1). Further, the lever 115 has the same basic construction as the lever 21 according to the first embodiment, but is formed in a shape set so that the groove portion 21f (see Fig. 1) at an end tip of the Lever 21 is in alignment with the position of the round projection 111b. Support members 112a and 112a hang down from both longitudinal end portions of the first door 112 on one of its surfaces opposite to the front cover 113. The round protrusions 112b and 112c are formed vertically on both surfaces of the support members 112a and 112a parallel to a longitudinal direction of the first door 112. As shown in Fig. 24, the round protrusion 112b faces outward and the round protrusion 112c faces inward. Further, grooves 112d and 112d are respectively formed in portions of the first door 112 that are located on the sides of the support pieces 112a and 112a above the round protrusions 112c and 112c. Elongated holes 113a and 113a are formed in a direction perpendicular to a bottom surface of the front cover 113 on both of their inner side surfaces on the side of a front opening portion of the front cover 113. Grooves 113b and 113b are formed in underside edge portions of the front opening portion of the front cover 113 on the sides of these longitudinal holes 113a and 113a. The first door 112 is rotatably attached to the front cover 113 by fitting and inserting the round protrusions 112b and 112b into the respective longitudinal holes 113a and 113a of the front cover 113. A screw portion 114a of the torsion spring 114 is fitted into each of the round protrusions 112c and 112c. End portions 114b and 114b are engaged with the grooves 112d and 112d, respectively. The other end portions 114c and 114c come into contact with a lower surface of the front cover 113 or a lower surface of the base plate 3, etc. Each of FIGS. 25a to 25d is a cross-sectional view showing an internal structure of the main portion of the cartridge loading mechanism according to the eighth embodiment. 25a shows an arrangement state of the cassette loading mechanism before a cassette is inserted into the cassette loading mechanism. The front cover 113 is attached between a base plate 3 and a dust cover 17. Furthermore, the surface member 110 is attached to the cassette loading mechanism. At this time, the second door 111 is attached between the front cover 113 and the surface member 110 such that the second door 111 can be moved up and down. The first door 112 comes into contact with the surface member 110 due to the bias of the torsion spring 114, so that the cassette insertion opening 110a is covered by the first door 112. At this time, the second door is below the first door 112. Operation of the cassette loading mechanism according to this eighth embodiment will be described next. When the cassette 2 is inserted into the cassette insertion opening 110a, the first door 112 is rotated clockwise against the bias of the torsion spring 114 by pushing the cassette 2 with the round projection 112b serving as an axis, as shown in FIG 25b shown. When the cassette 2 is attached to the cassette holder 22 (see Fig. 8), the cassette 2 starts to be moved down as shown in Fig. 25c, and the first door 112 is pushed down accordingly. The round projection 112b is moved down along an elongated hole 113a. After the cassette 2 is pinched as shown in Fig. 25d, the second door 111 is moved up and the cassette insertion opening 110a is closed. Operation of the second door 111 to close the cartridge insertion opening 110a is similar to that in the case of the first embodiment shown in FIG. 8. Therefore, an explanation of this operation is omitted here. In accordance with the eighth embodiment constructed above, a center of rotation of the first door 112 is below the position of the cartridge insertion opening 110a. Therefore, when the cassette 2 is inserted into a cassette holder, the first door 112 is rotated on an underside and is located on a lower surface side of the cassette holder, so that a space that is on an upper side of the can be further reduced Cassette holder is located. When the cassette is inserted and the second door 111 is on the central axis of a small hole 110b of the sheet 110 that is designed to temporarily discharge the cassette, it is preferable to form a notch in a corresponding portion of the second door 111. In this case, an amount of cutting of the second door 111 can be reduced compared to the length of a groove formed in the first door 55 according to the third embodiment shown in FIGS. 13 and 14. In the construction of the cassette loading mechanism according to the eighth embodiment, the elongated holes 113a and 113a are integrally formed with the front cover 113. The front cover 113 and the first door 112 form a structural body, so that sufficient strength is required for both the front cover 113 and the first door 112, although the front cover 113 and the first door are thin. Therefore, both the front cover 113 and the first door 112 are formed by a technical plastic material that has a high mechanical strength, such as polycarbonate, ABS resin, etc. However, a sliding property of any of these materials is generally poor. Accordingly, a mutual coefficient of friction of the front cover 113 and the first door 112 is increased when the cartridge is repeatedly loaded and unloaded many times, so that there is a fear that the movement of both the front cover 113 and the first door 112 is reduced. This problem is solved according to the following ninth embodiment. 26 is a perspective view showing the structure of a front cover as a main portion of the ninth embodiment. Reference numerals 120 and 121 designate the front cover and a door guide, respectively. The ninth embodiment is designed such that portions of the front cover 113 that form the longitudinal holes 113a and 113a according to the eighth embodiment are detachably attached and can be replaced. 26, a recess portion 112a is formed on an underside of each of the two inner sides of the front cover 120, that is, in a root portion of each of these two inner sides. The recess portion 120a is also formed in a portion of a corner portion of an opening portion of a front of the front cover 120. Further, the recessed portion 120a is formed within a stepped portion 120b formed in an outer bottom portion of the front cover 120. The door guide 121 is formed in a T shape as viewed from a front. The door guide 121 is constructed with a horizontal flat portion 121a and a vertical flat portion 121b vertically formed in the middle of the horizontal flat portion 121a. A longitudinal hole 121c, which corresponds to the longitudinal hole 113a (see FIG. 24) according to the seventh embodiment, is formed in the vertical flat portion 121b. The door guides 121 and 121 are arranged on both sides of the front cover 120 by fitting the horizontal flat portions 121a into the recess portion 120a. A material of the door guides 121 is slidably constructed with resin having a high sliding property such as polyacetal resin, nylon, etc. With such a structure, the peripheral portions of the elongated holes 121c and 121c can be formed by a member having a high sliding property so that a sliding property of the first door 112 with respect to the round protrusion 112b (see FIG. 24) is improved. Further, since the door guide 121 can be detachably attached to the front cover 120, the door guides 121 can be installed in the front cover 120 in a state in which the round protrusion 112b (see FIG. 24) of the first door 112 is fitted and is inserted into the longitudinal hole 121c. Accordingly, the efficiency of assembling the cassette loading mechanism is not reduced. With the cassette loading mechanism of the present invention constructed above, the following effects can be achieved. In a first construction of the present invention, it is possible to free up a space occupied by a general support arranged on the underside of a cassette holder. Accordingly, a dust-proof structure or a dust-proof structure is achieved by sealing perfectly and the body of the drive unit can be made thin. In a second construction of the present invention, an eject lever can be easily attached to the cassette loading mechanism. Accordingly, the effects of the cassette loading mechanism of the first construction can be obtained while minimizing an increase in the number of assembly operations. In the third embodiment of the present invention, an eject button can be easily attached to the cassette loading mechanism. Accordingly, the effects of the cassette loading mechanism of the first construction can be achieved while minimizing an increase in the number of assembling operations. Furthermore, an amount of play of the eject button is reduced, so that the body of the drive unit can be made thin and the operability of the drive unit can be improved. In a fourth construction of the present invention, the position of a rod contact portion of the eject button which comes into contact with an actuator and the position of a small hole of a front cover can be set to be deep compared to the general case, so that the Body of the drive unit can be made thin. In a fifth construction of the present invention, an end tip of a screw protruding from a screw holding portion and a back of the screw holding portion are fitted into a recess portion even when a first door is fully opened. Accordingly, the screw and the first door do not interfere with one another, so that the drive unit can be made thinner. In a sixth, seventh, eighth, or tenth construction of the present invention, a constricted portion is elastically deformed even if the nominal position of a lower end of the second door is located inside the front cover. Accordingly, the constricted portion absorbs scatter in the position of a groove portion. Therefore, it is possible to eliminate the disadvantage that a swing cam cannot be rotated. In a ninth construction of the present invention, the start time of a second door raising operation is delayed compared to the starting time of a cassette lowering operation at a cassette loading time. Accordingly, no finger is pinched through the second door even if the finger is delayed or hesitantly disconnected from the cassette. In contrast, when the cassette is ejected from the cassette loading mechanism, the timing for completing the lowering operation of the second door is faster than the timing for completing the lifting of the cassette. Accordingly, no cassette is engaged with the second door when the cassette is unloaded from the cassette loading mechanism. In an eleventh embodiment of the present invention, an escape section is formed in a lever, and a screw-holding section of a dust cover can be formed in a position corresponding to this escape section. Accordingly, in addition to the effects of the ninth embodiment, the dust cover and the front cover preferably come into close contact with each other, so that it is possible to reliably prevent dust from entering the cassette loading mechanism from the outside. In the twelfth construction of the present invention, only a tongue portion is bent when the cassette holder is attached to the swing cam so that the swing cam is not deformed. In the thirteenth construction of the present invention, a pin having a high surface roughness is smoothly inserted into a first hole so that the wear of the vibrating cam is not increased from a certain point in time. Thus, the cassette mounting / unloading life can be greatly increased. With the fourteenth construction of the present invention, a space located in an upper portion of the body of the drive unit can be reduced. With the fifteenth construction of the present invention, the assembling efficiency of the cassette loading mechanism is improved. Furthermore, it is possible to prevent an increase in the coefficient of friction between a rotating shaft of the first door and a bearing portion. The invention can be summarized, for example, as follows: The invention relates to a cassette loading mechanism in which a carrier is arranged on the top of a cassette holding device for storing or loading a cassette with a storage medium. A loading base is arranged on an upper side of this carrier. This cassette holder and the carrier are attached to a swing cam. Furthermore, this swing cam is swingably attached to the loading base part. The cassette holder is moved vertically in connection with horizontal movement of the carrier. The cassette holding device is moved back and forth between an insertion / unloading position of the cassette and a clamping position of a spindle motor. Thus, the body of a drive unit can be made thin while ensuring dustproofness.

Claims (15)

1. Cassette loading mechanism with:
a loading base;
a cassette holder for attaching a cassette that stores a storage medium therein;
a carrier for guiding the cassette holder to a predetermined position at an insertion or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base; and
a base plate for carrying or holding the loading base part; wherein the cassette loading mechanism is constructed such that the carrier is arranged on an upper side of the cassette holder, and
the swing cam is arranged such that the cassette holder is reciprocated vertically together with a reciprocating motion of the carrier in a direction approximately equal to an insertion / unloading direction of the cassette. 2. Cassette loading mechanism according to claim 1, characterized in that the cassette loading mechanism further comprises:
an eject button for receiving or receiving a biasing force of the cassette in its insertion direction by means of an actuator or an actuating tool from outside the cassette loading mechanism;
an eject lever having a hole portion in its central portion configured such that one end portion of the eject lever is connected to the eject button and the other end portion of the eject lever is engaged with the carrier to move the carrier in the unloading direction of the cartridge ;
a stepped pin which is attached to the loading base and rotatably supports the ejection lever through the hole portion; and
biasing means for biasing the eject lever so that the other end portion of the eject lever is rotated in a direction approximately equal to a direction of movement of the carrier at a time when the cassette is being loaded;
the perforated portion being formed by a first perforated portion through which it is possible to pass a head portion of the stepped pin and a second perforated portion connected to the first perforated portion and fitted to a shaft portion of the stepped pin ; and
wherein the ejection lever is attached to the stepped pin such that a direction directed from a center of the second hole portion to a center of the first hole portion approximately coincides with a biasing direction of the biasing means. 3. A cassette loading mechanism according to claim 2, characterized in that a lever pin is vertically attached to an end portion of the eject lever;
a hole for inserting the lever pin therein is formed in a portion of the eject button;
a groove portion is formed in a side surface of the eject button;
the groove portion of the eject button engages the loading base; and
a holding portion is formed to slidably carry the ejection button along the insertion direction of the cartridge. 4. Cassette loading mechanism according to claim 2, characterized in that a front cover with a cassette insertion opening for inserting and taking out the cassette is arranged in front of a cassette receiving opening of the cassette holding device;
a first door for opening and closing the cassette insertion opening by a turning operation is arranged near this front cover;
the eject button is positioned after the first door when the cartridge is inserted into the cartridge insertion opening;
a small hole for inserting an operating tool or an operating device therein is formed in the front cover;
a contact portion for receiving an end tip of the actuating device or the actuating tool is formed in the eject button; and
a groove portion is formed on a portion of a virtual line connecting the small hole to the contact portion on a rear surface of the first door that comes into contact with the cartridge when the cartridge is inserted. 5. A cassette loading mechanism according to claim 4, characterized in that a screw-holding portion for attaching the loading base is formed in each of four top corners of the base plate;
a first extension that comes into contact with an end tip of the cartridge is formed on a cartridge insertion side surface of the first door;
a position of this first extension is set to a position opposite to the screw retaining portion on a front side when the first door is fully opened at a cassette insertion or unloading time; and
a recess portion is formed on a back surface of the first extension. 6. Cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that stores a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at an inserting or discharging time of the cassette; and
a base plate for carrying or holding the loading base part;
wherein the cassette loading mechanism is constructed such that a first door for closing the cassette insertion opening is rotatably disposed in the vicinity of a front cover at a cassette unloading time;
wherein a second door for closing the cartridge insertion opening is slidably disposed in a direction perpendicular to a cartridge insertion / unloading direction at a cartridge loading time;
a lever for moving the second door by rotating this lever in association with movement of the bracket is arranged; and
a flexible or bendable section is formed in this lever. 7. Cassette loading mechanism according to claim 6, characterized in that the flexible section in the form of a leaf spring is formed by a Constriction is formed in a section of the lever. 8. Cassette loading mechanism according to claim 6, characterized in that the flexible section in the form of a leaf spring is formed by a notch is designed such that the notch is a center of rotation of the lever of surrounds its outside or outside. 9. Cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that receives a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at an insertion or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base; and
a base plate for carrying or holding the loading base part;
wherein the cassette loading mechanism is constructed such that a first door for closing a cassette insertion opening is rotatably disposed in the vicinity of the front cover at a cassette unloading time;
wherein a second door for closing the cassette insertion opening is slidably disposed in a direction perpendicular to an insertion-unloading direction of the cassette at a loading time of the cassette;
an extension is formed in a portion of the swing cam and extends in a diametrical direction to a state where an attachment portion of the swing cam is fixed to a center on the loading base;
a lever has a groove portion in an end tip portion thereof, and this groove portion is engaged with a round projection portion formed on at least one of the right and left sides of the second door;
said lever also having a shaft on a side opposite to said end tip portion, and said shaft extending in the same shaft direction as the mounting portion of the swing cam;
this lever is rotatably attached to a hole formed on at least one of the right and left side surfaces of the base plate so that the lever is moved in association with vertical movement of the second door;
a first cam portion, a notch portion and a second cam portion are formed in the lever;
the end tip portion of the lever is in a position to fully open the second door;
the first cam portion comes into contact with the second extension of the swing cam in a position corresponding to a time when the cassette holder is in a position that provides a cartridge unloading condition;
the first cam portion is formed by a recess portion that is in the shape of an arc with a length like a radius from the attachment portion to the extension, the attachment portion being a center;
an end tip portion of the lever is in a position to fully close the second door;
the notch portion is fitted in the extension of the swing cam in a position corresponding to a time when the cassette holder is in a position that provides a state of loading of the cassette; and
the second cam portion contacts the extension from a fully open state of the second door to a closed state of the cartridge insertion opening when the lever is rotated. 10. Cassette loading mechanism according to claim 9, characterized in that a Constriction section in a lever is designed such that a width of this Lever partially in approximately a central portion thereof in the same direction how a direction of rotation of the lever is restricted. 11. Cassette loading mechanism according to claim 9, characterized in that a Dodge section to dodge a portion of a fastener that protrudes into the base plate, is formed in the lever when a cover member for Cover an outside of the loading base part to the base plate by one Fastener is attached. 12. Cassette loading mechanism with:
a loading base;
a cassette holder for mounting a cassette that receives a recording medium therein;
a carrier for guiding the cassette holder to a predetermined position at an insertion or ejection time of the cassette;
a swing cam for swingably attaching the cassette holder and the carrier to the loading base and a base plate for carrying or holding the loading base;
wherein the cassette loading mechanism is constructed such that a portion of the loading base for attaching the swing cam thereon is fixed to a tongue portion which is separate from another bent portion. 13. Cassette loading mechanism according to claim 9 or 12, characterized in
that a pin is in an attachment position of the loading base for attaching the swing cam thereon; and
the swing cam is rotatably attached to the loading base by fitting this pin into a hole formed in the swing cam. 14. Cassette loading mechanism with:
a loading base;
a cassette holder for attaching a cassette that stores a loading medium therein;
a carrier for guiding the cassette holder into a predetermined position at the time of inserting or ejecting the cassette;
a base plate for carrying or holding the loading base part;
a first door that freely rotates to open and close a cassette insertion opening and that closes the cassette insertion opening at a time when the cassette is removed or unloaded; and
a second door slidably attached to the cassette loading mechanism in a direction perpendicular to a cassette insertion / unloading direction so that the cassette insertion opening is closed at a time when the cassette is loaded . becomes;
wherein the cassette loading mechanism is constructed such that a rotating shaft is arranged as a center of rotation in each of the right and left lower outer sides of the first door;
a bearing portion for supporting the rotary shaft is disposed on an underside of the cartridge insertion opening;
biasing means for biasing the first door on one side of the cartridge insertion opening to which the cartridge loading mechanism is attached; and
the first door is turned down at the cassette insertion time. 15. Cassette loading mechanism according to claim 14, characterized in that the Storage section releasably attached to a body of the cassette loading mechanism can be and is formed by a material with a high sliding property.