Background of the Invention
This invention relates to a magnetic disc clutch mechanism for a magnetic disc apparatus of cartridge type.
A magnetic disc cartridge is composed of, as shown in FIG. 1; a magnetic disc 2 which is rotatively mounted in a plastic cartridge case 1; a disc hub 3 for also serving as an armature which is projected from an opening 1a of a bottom surface of the cartridge case 1 so as to be adapted to fix the rotation center of the magnetic disc 2; a latching lever 5, the back end of which is energized toward the inner bottom surface of the case 1 by virtue of a leaf spring 4, and the top end of which is energized against a flange portion 3a formed around the periphery of the disc hub 3 so as to fix the disc hub 3 to the inner bottom surface of the cartridge case 1.
In a conventional magnetic disc apparatus of cartridge type to drive this magnetic disc cartridge, the magnetic disc 2 is sustained within the case 1 in a floating manner described as follows. After fixing a spindle assembly to an inner bottom surface of a housing which defines a cartridge chamber and after inserting the cartridge in the chamber, if it is executed to close a door of the chamber, an operation of a link system and the like which is cooperative with the door makes the cartridge descend and thereby the bottom surface of the disc hub 3 is connected to a magnetic chuck of the spindle assembly. In addition, a release pin which is mounted on the inner bottom surface of the housing, projects into the cartridge and abuts to a guide pin 5a which is fixed to the latching lever 5 and further pushes the latching lever 5 upwardly. Thus the magnetic disc 2 is sustained within the case 1 in the floating manner.
However, this constitution has a drawback such that it becomes large-sided, because it needs to ascend and/or descend a horizontally supporting device of the cartridge which is inserted into the cartridge chamber itself.
Moreover, the cartridge should be inserted within the cartridge chamber with a little rattle in order to make it easy to insert the cartridge into the chamber. On the contary, if a distance between the cartridge and the spindle assembly is not large enough, the cartridge interferes with the spindle assembly in its inserting operation so that more elevation amount is needed. This results in that the device is much thicker.
Summary of the Invention
This invention is intended to simplify the loading mechanism of the disc cartridge and to constitute a device much thinner by ascending and/or descending the spindle assembly as opposed to the conventional magnetic disc apparatus mentioned above and by connecting the spindle assembly to the cartridge which is inserted within the cartridge chamber.
This invention, which is intended to attain these objects, is characterized in that a spindle assembly is vertically movable and is provided on a bottom surface of a housing in which a magnetic disc cartridge is adapted to be inserted, and that one end of a lever being slidable by virtue of open and/or close operations of a door which is arranged at a housing opening is cooperative with said spindle assembly so that the spindle assembly ascends to the cartridge in accordance with the door closing operation and descends from the cartridge in accordance with the door opening operation.
Brief Description of the Drawings
FIG. 1 is a perspective view of a magnetic disc cartridge in a disassembled state for illustrating a constitution of the magnetic disc cartridge.
FIG. 2 is a plan view of a first embodiment of the present invention.
FIGS. 3 to 5 are cross-sectional views taken along III--III line, IV--IV line and V--V line of FIG. 2 respectively.
FIGS. 6A and 6B are perspective views of a second embodiment respectively.
Description of Preferred Embodiments
FIGS. 2 to 5 illustrate a first embodiment respectively. In each of the drawings, on the a center of an inner bottom surface or base of an end-opened housing 10, a cylindrical guide wall 12 is upstandingly provided and in an inner cylindrical portion of the cylindrical guide wall 12, a brushless direct current motor 14 of an outer-rotor type is provided.
A circumferential portion of the motor 14 is sustained by a guide block 16 which is slidably mounted within the inner cylindrical portion of the guide wall 12. At both of opposite sides of the guide block 16, a pair of arms 16a are integrally provided and extend protrusively through notches 12a which are formed on both of opposite sides of the guide wall 12.
On the other hand, on the inner bottom surface or base of the housing 10, a pair of levers 18 which are orthogonal to the arms 16a, are provided. Each of the levers 18 is slidably provided so as to be cooperative with open and/or close movements of a door or lid (not shown) which is secured to the opening of the housing 10 and each of the levers 18 is formed with a tapered shoe 18a at the slide surface where the arm 16a and the slide surface contact each other. Within the arm 16a, a release pin 20 which penetrates therethrough is disposed and on a circumference of a lower portion of the release pin 20, a compression coil-spring 22 is provided so as to normally bias the arm 16a in a downward direction.
Accordingly, in a state wherein the door or lid is opened, the motor 14 moves downward the under portion of the inner bottom surface of the housing 1 and thus the cartridge can be inserted into the housing. Further, if the cartridge is inserted and the door is closed, in accordance with the movement of the door, the lever 18 advances and pushes up the arm 16a along the taper surface of the shoe 18a.
Consequently, the motor 14 ascends together with the arm 16a so as to enable a positioning axis of the motor 14 do connect with the hub 3, and the motor 14 connects closely with the under surface of the hub 3 by virtue of a magnetic chuck 14b which is provided around the axis 14a. In accordance with this movement of the arm 16a, the release pin 20 ascends and pushes up the pin 5a sustaining the latching lever 5 so as to bring the latching lever 5 free from engagement with the hub 3. Thus, the magnetic disc 2 can be integrally rotative with the motor 14.
Moreover, on the upper edge of the inner peripheral portion of the guide wall 12, a taper portion 12b is provided and also, on the upper edge of outer peripheral portion of the guide block 16, a taper portion 16b is provided. Therefore, the elevated position of the motor 14 is stopped by the engagement of the taper portion 12b and the taper portion 16a. By virtue of this taper arrangement, the motor 14 can be fixed so that the center thereof is accurately aligned with the center of the guide wall 12.
In addition, on the intermediate portion of the arm 18, a long hole 18b is provided and on a part of the long hole 18b, as above described, a tapered shoe 18c is provided. On the bottom of the housing 10, there is provided with a positioning pin 26 which is normally located on the down position by virtue of the biasing force of a spring 24. On the upper portion of the positioning pin 26, there is provided a pin 28 which is engaged with the shoe 18c so as to push up the positioning pin 26 along the upper surface of said the shoe 18c.
The positioning pin 26 is correspondingly engaged with a positioning hole 1b which is penetratingly provided on the corner of the cartridge case 1, and can position the cartridge 1 within the housing when door is closed by engaging with the positioning hole 1b.
FIG. 6A and FIG. 6B illustrate a second embodiment. In the drawings, on both of the opposite sides of a guide sleeve 40, a pair of cam grooves 40a are provided at rotational symmetric positions. While, on the outer peripheral portion of the motor 14, pins 42a, 42b are protrusively provided so as to be adapted to engage with the cam grooves 40a respectively. Further, one of the pins 42b can engage with a top end of a lever 44 which is slidable in accordance with the open and/or close operation of the door (not shown).
The top end of the lever 44 is composed of a fixing member 46 for interposingly sustaining the pin 42b, a pushing member 48 for pushing the pin 42b, and a spring 50 which is mounted within the lever 44 and can normally forcibly urge the pushing member 48 against the fixing member 46.
FIG. 6A illustrates the state in which the door is opened. In this state, the pin 42b positions at the lowest position of the cam groove 40a. Thus, the motor 14 descends under the guide sleeve 40 and the positioning axis 14a is located lower than the upper portion of the guide sleeve. From this state, if the lever 44 advances, the motor 14 slides rotatively on the cam groove 40a by virtue of the lever of the pin 42 so that as shown in FIG. 6B, the motor is transferred upwardly.
Furthermore, in this embodiment, a release pin and a positioning pin are omitted respectively, but these parts can be installed as in the first embodiment. Also, in this embodiment, taper connecting means can be used as means for limiting the elevation position of the motor as in the first embodiment.
In addition, this invention is not limited to these embodiments and various modifications can be carried out within the range of the claims.
This invention is constituted as set forth above such that on comparison with the conventional apparatus wherein the cartridge side is moved up and down in accordance with the open and/or close operation of the door, the mechanism of the driving portion can be simplified and the device can be made thinner and more compact.