JPH0710839U - Magnetic disk unit - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a magnetic disk drive capable of smoothly operating the chucking mechanism of a floppy disk even when the ejecting lever has a weak return spring force, and which can reduce the overall size. [Structure] An inclined cam 3 to which an operation pin 32 for vertically moving a chucking mechanism 8 of a floppy disk is elastically contacted
1, the first cam surface 31a having a steep slope and the first cam surface 31a
A magnetic disk drive characterized in that a second cam surface 31b having a gentler slope is continuously formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a magnetic disk device such as a personal computer and a word processor, and more particularly, to an improvement of a tilt cam to which an operating pin for vertically moving a chucking mechanism of a floppy disk is elastically contacted.

[0002]

[Prior art]

 Generally, a magnetic disk device is provided with a chucking mechanism for attaching / detaching a floppy disk, and in a normal case, the chucking mechanism is equipped with a spindle and a collet for holding the floppy disk, and the elevating and lowering of the collet is carried out by an eject lever. It is controlled via a collet lifting arm by a tilting cam that operates in conjunction with the movement.

Further, when a floppy disk is inserted into such a conventional magnetic disk device to be checked, the first operation is performed until the collet comes into contact with the peripheral edge of the holding portion of the floppy disk as the eject lever returns. Since there is no load during the period, the collet lifting arm can be lowered with a comparatively weak force, but after the collet abuts on the peripheral edge of the holding part of the floppy disk, the collet is inserted into the recess of the spindle. In the second period for securely holding the floppy disk, a considerably large pressing force is required when the collet is inserted.

That is, in order to raise and lower the collet that holds the floppy disk, conventionally, as disclosed in, for example, Japanese Utility Model Laid-Open No. 4-126344, the eject lever is locked when the floppy disk is inserted. It is proposed that the cam follower pin provided at the end of the collet elevating arm be mounted on the upper end surface of the inclined cam that operates in conjunction with the operation of the eject lever while releasing the eject lever and returning the eject lever by the return spring. This inclined cam is formed with the same inclined surface in both the first period and the second period.

[0005]

[Problems to be solved by the device]

 However, in the same magnetic disk drive in which the cam follower pin of the collet lifting arm is mounted on the upper end surface of the cam formed by the same inclined surface, the return spring force sufficient for the cam follower pin to mount on the inclined cam surface during the second period. However, if the tilt angle of the cam is increased, the length of the cam surface and the operating stroke of the eject lever can be shortened, but the spring force of the return spring for returning the eject lever also becomes stronger, making the floppy disk The operation when inserting and ejecting becomes difficult, and the work of assembling the return spring to the eject lever becomes difficult.

On the other hand, if the inclination angle of the cam is made conversely gentle, the return force (spring force) of the eject lever can be weakened to facilitate the operation, but under the condition that the inclination angle of the cam is constant, the cam surface Since it is necessary to increase the length and the stroke of the eject lever, it becomes difficult to miniaturize the magnetic disk device, and during the first period, the collet suddenly descends to damage the peripheral edge of the holding part of the floppy disk. There is.

In view of the above-mentioned conventional problems, the purpose of the present invention is to enable the chucking mechanism of a floppy disk to be operated smoothly even if the ejecting lever has a weak returning force, and the overall size is reduced. It is to obtain a magnetic disk device that can be miniaturized.

[0008]

[Means for Solving the Problems]

 To achieve this object, the present invention provides a steeply inclined first cam surface and a gentler gradient than the first cam surface to an inclined cam to which an operating pin for vertically moving a chucking mechanism of a floppy disk is elastically contacted. The present invention proposes a magnetic disk device in which the second cam surface having the above is continuously formed.

[0009]

[Action]

 According to the magnetic disk device of the present invention thus constructed, the collet slowly descends while the operating pin for vertically moving the chucking mechanism of the floppy disk moves along the steeply inclined first cam surface. And collide with the spindle, and while the actuating pin moves along the second cam surface that has a gentler slope than the first cam surface, the collet further abuts on the spindle, and then the collet further descends, resulting in a weak return. The actuating pin can be moved along the second cam surface by the spring force, and the pressing force for holding the floppy disk can be obtained.

[0010]

【Example】

 Hereinafter, details of an embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a top view of a 5-inch magnetic disk device according to the present invention with a top cover removed, and FIG. 4 is a bottom view of the same magnetic disk device.

First, in the 5-inch magnetic disk device 1, a bottom main frame 4 and a top sub-frame 5 are assembled to the left and right mounting plates 2 and 3 via a spacer (not shown) to form a chassis. Various printed circuit boards 6 and electronic parts are fixed to the main frame 4 and the sub frame 5 of this chassis.

Then, a 5-inch floppy disk 50 can be loaded into the magnetic disk device 1 from the insertion port of the front panel 7 attached to the front surface. Further, the above-mentioned magnetic disk device 1 includes a chucking mechanism 8 for holding the floppy disk 50 at a driving position, and a magnetic disk for recording a predetermined signal on the upper and lower surfaces of the magnetic disk of the floppy disk 50 and reading a recorded signal. A head unit 10 having a head 9, a head sliding mechanism 11 for moving the head unit 10 in the direction of arrow B toward the center of the inserted floppy disk 50, and chucking in association with the operation of the eject button 12. The mechanism 8 includes a first swing arm 13 for moving the collet up and down, and a second swing arm 14 for moving the head unit 10 to and from the surface of the floppy disk 50.

In the head portion 10 of the 5-inch magnetic disk device 1, the rear portion of the upper carriage 15 and the rear portion of the lower carriage (not shown) are connected by a leaf spring 16, and the upper surface of the upper carriage 15 is It is pressed downward by one hook of the torsion spring 17. Further, the protruding piece 15a formed on the upper carriage 15 is engaged with the upper surface of the second swing arm 14, and the upper carriage 15 moves in the vertical direction in response to the vertical movement of the second swing arm 14. You can swing.

A head sliding mechanism 11 for moving the head portion 10 in the front-back direction is slidably assembled to a traveling member 20 engaged with a spiral groove of a lead screw 19 rotated by a stepping motor 18 and a guide shaft 21. It is constituted by the traveling guide member 22 attached.

The chucking mechanism 8 of the magnetic disk device 1 is actuated by a first swing arm 13 which moves up and down in association with the operation of an eject button 12, and is formed on a side edge of the first swing arm 13. The protruding piece 13 a can engage with the upper surface of the second swing arm 14. The first swing arm 13 and the second swing arm 14 are pivotally supported on the subframe 5 via support shafts 25 and 26, respectively, and are urged upward by the coil springs 23 and 24. A collet (not shown) of the above-mentioned chucking mechanism 8 is supported by a leaf spring 27 fixed to the tip of the first swing arm 13.

The eject lever 28, to which the eject button 12 is fixed at the tip, is attached to the lower surface of one side of the main frame 4, and the rack 28 a formed at the rear end of the eject lever 28 has a damper. It is engaged with the pinion 29a of 29 and is urged in the direction of arrow Y via the return spring 30. As shown in FIG. 1, an inclined cam 31 is integrally formed in the middle of the eject lever 28. The inclined cam 31 has an operating pin 32 for vertically moving the first swing arm 13. It will be hit.

As shown in FIG. 2, the inclined cam 31 of the eject lever 28 has a first cam surface 31 a having a steep slope during a stroke m and a portion looser than the first cam surface 31 a during a stroke n. A second cam surface 31b having a slope and a flat upper end surface 31c are continuously formed. Therefore, by the operation of the eject lever 28, the chucking mechanism 8 of the floppy disk 50 and the upper carriage 15 of the head portion 10 are moved up and down while the operation pin 32 of the first swing arm 13 moves on the cam surface of the inclined cam 31. It

That is, the first cam surface 31a of the inclined cam 31 moves to the other side of the first swing arm 13 while the operation pin 32 of the first swing arm 13 moves a stroke m along the first cam surface 31a. The collet installed on the end side has a height corresponding to the first period until the collet descends from the highest position and contacts the spindle. Also, the second cam surface 31b of the inclined cam 31 has a collet that comes into contact with the spindle while the operation pin 32 moves along the second cam surface 31b and then moves downwardly. The height is set to correspond to the second period in which the pressing force for holding the disc 50 is obtained.

Next, the operation of the magnetic disk device configured as described above will be described. First, when the floppy disk 50 is inserted from the insertion port of the magnetic disk device 1, the eject lever 28 is unlocked and the return spring 30 causes the eject lever 28 to return in the Y direction on the front surface of the main body.

The actuating pin 32 of the first swing arm 13 elastically contacting the inclined cam 31 of the eject lever 28 moves along the first cam surface 31 a and the second cam surface 31 b of the inclined cam 31. While riding on the upper end surface 31c, the other end of the first swing arm 13 is pushed down against the spring 23. Further, in conjunction with this, the other end side of the second swing arm 14 engaged with the first swing arm 13 is pushed down against the spring 24.

At this time, the actuating pin 32 of the first swing arm 13 elastically contacting the inclined cam 31 of the eject lever 28 moves the stroke m along the steeply inclined first cam surface 31a. The collet of the chucking mechanism 8 installed on the other end side of the swing arm 13 is slowly lowered and brought into contact with the spindle. Further, since the operating pin 32 moves the stroke n along the second cam surface 31b having a gentler slope than the first cam surface, even after the collet is brought into contact with the spindle even if the return spring force of the return spring 30 is weak. Further, the operation of lowering the collet can be performed smoothly, and the taper portion of the collet penetrates the central opening of the hole 51a of the floppy disk 50 and fits into the recess of the spindle hub to center the floppy disk 50.

Further, when the actuating pin 32 of the first swing arm 13 rides on the upper end surface 31 c of the inclined cam 31, the collet supported by the leaf spring 27 of the first swing arm 13 is elastically moved by the leaf spring 27. It is pushed down further to obtain a pressing force for holding the floppy disk 50, so that the flange portion of the collet and the upper end surface of the spindle hub hold the peripheral edge portion of the hole 50a of the floppy disk 50. Has become.

The second swing arm 14 that is engaged with the first swing arm 13 via the protruding piece 13 a of the first swing arm 13 is also pushed down against the spring 24. The head portion 10 engaged with this can be brought into contact with the surface of the floppy disk 50.

On the other hand, when the eject button 12 is operated to eject the floppy disk 50 from the magnetic disk apparatus 1, the operation pin 32 of the first swing arm 13 is pushed by pushing the eject button 12 so that the eject lever is ejected. The inclined cam 31 of 28 descends along the inclined surface to the lower end surface thereof, and the other end of the first swing arm 13 is pushed upward by the spring 23.

Further, the second swing arm 14 linked to the first swing arm 13 is also pushed up by the spring 24 in conjunction with the first swing arm 13. Then, the upper carriage 15 of the head unit 10 is pushed up by the second swing arm 14, the chucking of the floppy disk 50 is released, and the floppy disk 50 is ejected from the insertion opening of the front panel 7 by the return lever. It will be.

[0027]

[Effect of device]

 As is clear from the above description, according to the magnetic disk drive of the present invention, the operation pin moves on the first cam surface of the inclined cam until the collet of the chucking mechanism abuts on the spindle. During the period of, the movement stroke of the tilt cam is short, the actuating pin can be pushed up smoothly and smoothly, and the collet can be prevented from dropping rapidly, and the floppy disk can be prevented from being damaged. Also, after the collet abuts the spindle, the second cam surface, which has a gentler slope than the first cam surface, pushes up the operating pin, so that even if the ejector lever return spring force is weak, the operating pin can be smoothly moved. Can be pushed up to the top surface.

Therefore, according to the present invention, the length of the cam surface of the inclined cam can be set short without increasing the stroke of the eject lever. Further, since the spring force of the ejector return spring can be weakened, the work of assembling the ejector return spring can be facilitated, and the floppy disk can be easily attached and detached.

[Brief description of drawings]

FIG. 1 is a perspective view of an eject lever used in the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a cam shape of the eject lever and an operating pin of a first swing arm.

FIG. 3 is a top view of a 5-inch magnetic disk drive according to the present invention showing a state in which a top cover is removed.

FIG. 4 is a bottom view of the magnetic disk device.

[Explanation of symbols]

 1 magnetic disk device 8 chucking mechanism 30 return spring 31 inclined cam 31a first cam surface 31b second cam surface 31c upper end surface 32 operating pin

Claims (1)

[Scope of utility model registration request] 1. An inclined cam to which an operating pin for vertically moving a chucking mechanism of a floppy disk is elastically contacted,
A magnetic disk drive characterized in that a first cam surface having a steep slope and a second cam surface having a gentler slope than the first cam surface are continuously formed.