JPS633019Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a disc-shaped rotating body having a rotating shaft insertion hole approximately in the center and having a position regulating pin insertion hole at a position offset from the rotating shaft insertion hole;
It consists of a rotary shaft that rotates around its axis and a rotation drive mechanism that has a position regulating pin that is attached to a position that can be biased away from the rotary shaft, and the position regulating pin has a positioning surface and a driving surface. The rotating shaft is inserted into the position regulating pin insertion hole having The rotating body is inserted into the rotating shaft insertion hole having a positioning surface, and is crimped and engaged with the positioning surface by the urging force of the position regulating pin, thereby positioning the rotating body with respect to the rotating shaft. This invention relates to a rotational drive device.

A disk cassette consisting of a flexible disc-shaped disk (so-called magnetic sheet) housed in a flat cassette housing is attached to the main body of the recording/reproducing apparatus, the magnetic disk is rotated at high speed, and the magnetic head is Conventionally, devices have been known in which video signals, audio signals, or digital signals are recorded and reproduced by being brought into contact with the magnetic surface of a magnetic disk while being moved in the radial direction of the disk.

1 to 10 are for explaining a disk rotation drive device in a disk type recording/reproducing device to which the present invention can be applied. 1
The magnetic disc cassette 6 is comprised of a disk cassette 6 in which a magnetic disk 1 is housed, and a rotational drive mechanism that rotationally drives the magnetic disk 1 within the disk cassette 6.

As shown in FIG. 1, the magnetic disk 1 is, for example,
The magnetic recording medium is made of a thin disc-shaped polymer film with a thickness of 0.04 mm, and a magnetic layer is uniformly formed on the lower surface on which the recording/reproducing magnetic head slides. Further, a circular central opening 1a is provided at the center of the magnetic disk 1 (see FIG. 3), and a core metal 3 made of a magnetic material such as iron is attached to this central opening 1a. This core metal 3 is made by pressing a single disk, and as shown in FIGS. 1 and 3, it has a disk-shaped recess 3a on one side and a disk-shaped protrusion on the other side. 3b, and a ring-shaped flange 3c is provided on the peripheral edge of the core metal 3, so that it has a so-called dish-shaped configuration. As shown in FIG. 3, the flange 3c of the core metal 3 has a protrusion 3.
A ring-shaped double-sided adhesive sheet 7 is adhered to the side b, and the peripheral edge of the central opening 1a of the magnetic disk 1 is adhered to this double-sided adhesive sheet 7. Thereby, the core metal 3 and the magnetic disk 1 are integrally coupled.

As clearly shown in FIG. 2, a substantially square motor shaft insertion hole 4 is formed in the center of the core metal 3, and a rectangular position control is provided at a position offset from the insertion hole 4 by a predetermined distance. A pin insertion hole 5 is formed. In addition, the above-mentioned motor shaft insertion hole 4
The center O ₁ of is deviated from the center O ₂ of the core metal 3 and thus the magnetic disk 1 and is slightly offset by a predetermined distance toward the position regulating pin insertion hole 5 side. Further, a pair of diagonal lines d ₁ and d ₂ of the motor shaft insertion hole 4 are configured to be parallel to a pair of mutually opposing sides of the position regulating pin insertion hole 5, respectively. Furthermore, since the length of one side of the insertion hole 4 is configured to be longer than the diameter of the motor shaft to be inserted into the insertion hole 4, the motor shaft may be inserted into the insertion hole 4 with some wobbling. It is becoming more and more like this.
The reason why the center of the insertion hole 4 is offset from the center of the core metal 3 in this way will be explained in detail later, but when the disk cassette 6 is installed in the main body of the device, the core metal 3
This is to align the axis of the motor shaft inserted into the insertion hole 4 with the center of the magnetic disk 1.

On the other hand, as shown in FIG. 1, the cassette housing 2 for housing the magnetic disk 1 is composed of an upper half 2a and a lower half 2b made of injection molded ABS resin containing an antistatic agent, for example. The outer peripheries of these upper and lower halves 2a, 2b are welded to each other to form a flat rectangular parallelepiped shape as a whole. Further, a circular central opening 8 is provided approximately in the center of the lower half 2b, and a ring-shaped protrusion 9 is integrally formed on the periphery of the central opening 8 and on the inner surface of the lower half 2b. As shown in the figure, the protrusion 3b of the core metal 3 is fitted into the central opening 8 with some play due to the gap between the two (for example, about 0.7 mm). Furthermore, a ring-shaped protrusion 1 is provided on the inner surface of the center portion of the upper half 2a.
0 is integrally molded, and a ring-shaped protrusion 11 that is concentric with the protrusion 10 is provided around the outer periphery of the protrusion 10.
is integrally molded. Note that the protrusion length of the protrusion 10 described above is longer than that of the protrusion 11, so the protrusion length of the protrusion 10 is longer than that of the protrusion 11.
0 protrudes beyond the protrusion 11 and toward the inner surface of the lower half 2b, as shown in FIG. The ring-shaped protrusion 10 is inserted into the recess 3a of the core metal 3 with some play.
Further, on the inner surfaces of the upper and lower halves 2a and 2b, for example, four arcuate ribs 13 and 14 extending concentrically with respect to the central opening 8 are integrally molded at equal intervals. And upper and lower halves 2a, 2
When the cassette housing 2 is assembled by overlapping the ribs 13 and 14 of the upper half 2a and the lower half 2b, the ribs 13 of the upper half 2a and the ribs 14 of the lower half 2b are arranged on the same circumference, and the four ribs of the cassette housing 2 At the corners, the ribs 13 and 14 are arranged adjacent to each other, thereby forming essentially one rib at each corner. The magnetic disk 1 is arranged so as to be surrounded by these ribs 13 and 14. Further, the rib 13 is provided on the inner surface of the lower plate 2d of the lower half 2b, and the rib 14 is provided on the inner surface of the lower plate 2d of the lower half 2b.
The cassette housing 2, which is flat and easily deformed even by a small external force, is thereby mechanically reinforced. Furthermore, in order to prevent the magnetic disk 1 from being damaged or worn out, the upper and lower halves 2a and 2b are provided with protective sections between the protrusion 11 and the rib 13, and between the protrusion 9 and the rib 14. Nonwoven fabric 15a, 15
b are attached by heat welding or the like.

The upper and lower halves 2a, 2b of the cassette housing 2 and the lower fabrics 15a, 15b have long holes 16, 1 extending in the radial direction of the magnetic disk 1 and having the same shape as each other.
7 and 18 are formed respectively, and these long holes 1
6, 17, and 18 are arranged facing each other and overlapped. The magnetic head is inserted into the long hole 17 of the lower half 2b through the long hole 18 of the lower nonwoven fabric 15b, and the magnetic head is inserted into the long hole 1 of the upper half 2a.
6, a disk holding pad can be inserted through a long hole 18 (not shown) in the upper nonwoven fabric 15a. In addition, in Figure 1, 1
Reference numerals 9a and 19b are positioning projections that are fitted into each other when the upper and lower halves 2a and 2b are combined.

Next, the structure of the recording/reproducing apparatus main body 20 to which the disk cassette 6 as described above is installed will be explained with reference to FIGS. 4 to 9.

As shown in FIG.
Book cassette receiving pins 23, 24, 25, 26
is installed, and this disk cassette 6-4
The two corners are adapted to be received by these pins 23-26. And a pair of support shafts 2
It is configured to be held in a predetermined position by being pressed from above by a cassette holding member 29 which is rotatably attached to the chassis 22 about 7 and 28.

The chassis 22 also includes a rotational drive mechanism 30 for rotationally driving the magnetic disk 1 in the disk cassette 6.
is provided. That is, the cassette receiving pin 2
A flat brushless motor 31 for rotationally driving the magnetic disk 1 within the cassette housing 2 is fixed approximately at the center of the area surrounded by 3 to 26. As shown in FIG. 5, on the upper surface of the rotor 32 of this motor 31, there is a spacer 33 formed by missing a part of a ring-shaped disk, and a spacer 33 for regulating the position (centering) of the magnetic disk 1 in the cassette case 2. A pair of setscrews 3 include a leaf spring member 35 to which a position regulating pin 34 is fixed, and a disc-shaped yoke 37 having a ring-shaped recess 36 on the upper surface.
8 are fastened together. The above-mentioned leaf spring member 3
5 is interposed between the spacer 33 and the yoke 37, and the spacer 33, the plate spring member 35 and the yoke 3
7 are further fastened together with one set screw 39. Therefore, these are designed to be rotationally driven together with the motor shaft 31a of the motor 31.

This leaf spring member 35, as shown in FIG.
An opening 40 having an approximately horseshoe shape is provided approximately at the center thereof. A pin attachment portion 43 is integrally formed on this leaf spring member 35 via a pair of narrow L-shaped arm portions 42, and this pin attachment portion 43 is attached to the above-mentioned pair of arm portions 42. Therefore, it is supported on both sides. The previously described position regulating pin 34 is fixed to this pin attachment portion 43. That is, as shown in FIGS. 6 to 8, the position regulating pin 34 includes a shaft portion 45 having a flange 44 approximately in the center, a bearing portion 46 that is fitted and fixed to the upper end of this shaft portion 45, and A cylindrical portion 48 is rotatably attached to the shaft portion 45 by a ball bearing 47 disposed between the cylindrical portion 48 and the bearing portion 46 . The shaft portion 45 passes through the pin attachment portion 43, and a cylindrical attachment member 49 is fitted and fixed to the lower end portion of the shaft portion 45 passing through the pin attachment portion 43. and shaft part 4
The pin attachment portion 43 of the leaf spring member 35 is held between the flange 44 of No. 5 and the attachment member 49, and thereby the position regulating pin 34 is fixed to the pin attachment portion 43. The cylindrical portion 48 of the position regulating pin 34 passes through an opening 50 provided in the recess 36 of the yoke 37, and the cylindrical mounting member 49 passes through the rotor 32. Therefore, this pin 34 can be biased within the opening 50 in the direction of arrow A in FIG. It is rotatable in the directions of arrows B and C about the arm portion 42 (in other words, movable in the radial direction of the yoke 37). Note that the pin 34 is attached at a position such that the distance S ₁ shown in FIG. 6 is slightly longer than the distance S ₂ shown in FIG. 10.

On the other hand, as shown in FIG.
Four pairs of magnets 52 are adhesively fixed within the magnet 6 at approximately equal intervals in the circumferential direction using an adhesive or the like. On the upper surfaces of the inner and outer flanges 37a and 37b of the yoke 37, a slippery sheet 53 made of a Teflon sheet mixed with carbon, etc.
54 are attached to each. Note that the upper surface of the slippery sheets 53 and 54 (i.e., the receiving surface of the core metal 3)
are arranged on the same plane with each other and above the upper surface of the magnet 52, as shown in FIGS. It protrudes upward from the top surface.

In FIG. 4, reference numeral 55 denotes a motor cover, in which a yoke 37 is rotatably disposed in an opening 56 provided on the upper surface of the motor cover 55, and a slider affixed to the yoke 37 is provided. The elastic sheets 53 and 54 protrude upward from the upper surface of the motor cover 55.

Next, the fourth head moving device of the device main body 20 is attached.
This will be explained with reference to FIG. 9 and FIG.

This head moving device includes a head support base 6 to which a magnetic head 58 is fixed via a mounting plate 59.
0 and a feed screw 62 which is rotated about its axis by a step motor 61. A step motor 61 is screwed to the vertical piece 63 of the chassis 22, and a motor shaft 61a of the step motor 61 is directly connected to the feed screw 62. The other end of the feed screw 62 is rotatably attached to a cut and raised piece 64 of the chassis 22, and the feed screw 62 is arranged horizontally with respect to the chassis 22.

Further, in this example, the head support base 60 is configured to be movable along the axial direction of the feed screw 62. That is, the chassis 22 is provided with a pair of guide shaft attachment portions 65 and 66, and these attachment portions 65 and 66 are provided with a guide shaft 67 having a circular cross section.
is fixed at both ends. Note that this guide shaft 6
7 is arranged parallel to the feed screw 62.
The guide shaft 67 passes through the head support base 60 and is supported by a sleeve 68 attached to the head support base 60. Therefore, the head support base 60 supports the guide shaft 67.
arrows D and E in FIG.
It is configured to slide in the direction.

On the other hand, as shown in FIGS. 4 and 9, a pair of needle-like member attachment portions 71 are integrally molded on the head support base 60, and are opposed to each other with a gap between them. The feed screw 62 passes through an opening 72 provided in the vertical piece 63 of the head support base 60, and is disposed between the pair of needle-like member mounting portions 71. On the upper surface of the pair of mounting parts 71,
A V-shaped groove 73 having an inclination corresponding to the pitch angle of the threaded portion of the feed screw 62 with respect to the direction perpendicular to the axis of the feed screw 62 and extending along the same straight line.
a and 73b are provided, respectively. Then, with both ends inserted into these V-shaped grooves 73a and 73b, the needle-like member 74 is attached to the pair of attachment portions 71.
It is inserted between the threads of the feed screw 62 (that is, the thread valley) and along the threads without play. The needle member 74 is fixed to the mounting portion 71 in the above-described arrangement by tightening a presser plate 75 on the upper surface of the needle member 74 to the upper surface of the mounting portion 71 with a pair of set screws 76. Further, as shown in FIG. 9, a leaf spring 77 is fastened together with the set screw 76 on the lower surface of the mounting portion 71 on one side, and is fed by the elastic restoring force of the free end of the leaf spring 77. The screw 62 is always energized toward the needle-like member 74 and the holding plate 75 side. Therefore, the needle-like member 74 and the threaded portion of the feed screw 62 never come out of engagement, and moreover, the needle-like member 74 always engages with the threads adjacent to each other without wobbling.

Further, as shown in FIG. 4, a pad support member 79 provided with a pad 78 made of felt or the like is rotatably attached to the head support base 60. That is, the head support base 60 is provided with a pair of vertical pieces 80 extending perpendicularly to the chassis 22 and facing each other, and each of these vertical pieces 80 is provided with a bearing. A shaft 81 fixed to the pad support member 79 is supported by the above-mentioned bearing (not shown), and a compression coil spring 82 is installed between the vertical piece 80 on one side and the pad support member 79. Therefore, the pad support member 79 is moved in the direction of arrow F in FIG.
It is constantly energized in the direction of crimping. Note that when the disk cassette 6 is not attached to the main body 20 of the apparatus, a predetermined biasing mechanism (not shown) causes the pad support member 79 to move in the direction indicated by the arrow in FIG. 4 against the biasing force of the compression coil spring 82. Since it is energized in the G direction, the pad 78 is separated from the magnetic head 58. Therefore, FIG. 4 shows disk cassette 6.
2 shows the state of the device main body 20 when it is not attached. When the disk cassette 6 is installed, the pad support member 79 is supported by the compression coil spring 8.
As a result, the magnetic disk 1 exposed in the long holes 16 and 17 of the cassette housing 2 is held between the pad 78 and the magnetic head 58. It is configured.

Next, the operation of the recording/reproducing apparatus configured as above will be explained.

First, the disk cassette 6 is attached to the cassette receiving pin 2 of the device main body 20 using a cassette mechanism (not shown).
3 to 26. In conjunction with this, the cassette holding member 29 rotates about the support shafts 27 and 28 in conjunction with the cassette mounting mechanism, whereby the cassette holding member 29 holds the disc cassette 6.
is elastically pressed downward. As a result, the disk cassette 6 is elastically held between the cassette holding member 29 and the cassette receiving pins 23 to 26 and held in a positionally regulated state.

On the other hand, the portion of the disk cassette 6 on the side where the long holes 16 and 17 are provided has the magnetic head 58 and the pad 7.
It is inserted between 8 and 8. The pad support member 79 is rotated in the direction of arrow F in FIG. 4 by the biasing force of the compression coil spring 82 in conjunction with the mounting operation of the disk cassette by a biasing mechanism (not shown). Long hole 16,1 in body 2
A portion of the magnetic disk 1 exposed through the magnetic head 58 and the pad 78 is held between the magnetic head 58 and the pad 78, respectively.

As the disk cassette 6 is mounted in this manner, the core metal 3 fitted into the center opening 8 of the lower half 2b of the disk cassette 6 is attracted by the magnet 52 of the yoke 37 and is attached to the yoke 37. It is adsorbed onto the slippery sheets 53 and 54 of. At the same time, the motor shaft 31a of the motor 31 is inserted into the motor shaft insertion hole 4 of the core metal 3.
If the positions of the position regulating pin insertion hole 5 of the core bar 3 and the position regulating pin 34 are shifted from each other,
This pin 34 is pressed downward by the core metal 3 due to the suction force acting between the core metal 3 and the magnet 52. As a result, the pin 34 is pushed downward against the elastic restoring force of the leaf spring member 35, particularly the arm portion 42, as shown by the solid line in FIG. Under such conditions, the device body 20
is switched to recording or playback mode and motor 3
When the first motor shaft 31a is rotationally driven, the position regulating pin 34 rotates together with the leaf spring 35 and the yoke 37 with respect to the core metal 3. That is, as described above, the magnetic disk 1 is held between the magnetic head 58 and the pad 78, whereby the magnetic disk 1 is held between the magnetic head 58 and the pad 78.
Since the load torque is acting on the yoke 37,
Even if frictional force acts between the slippery sheets 53 and 54 attached to the core metal 3 and the core metal 3 and the position regulating pin 34, the core metal 3 is not rotated and the pin 34 remains stationary. It rotates relative to the core metal 3 in the state. Thereafter, when the pin 34 rotates and reaches the position regulating pin insertion hole 5 of the core metal 3 as shown by the imaginary line in FIG. Therefore, it enters into the insertion hole 5.

As the motor shaft 31a rotates in the direction of arrow H, the pin 34 further rotates, and the cylindrical portion 48 of the pin 34 is inserted into the long side of the pair of long sides of the insertion hole 5 that is far from the motor shaft 31a. 5a first. Note that this long side 5a is a positioning surface. Next, the pin 34 is further rotated, but at this time, the clamping force of the magnetic head 58 and the pad 78 and the inertia force due to the difference in rotational speed between the yoke 37 and the core metal 3 are applied to the magnetic disk 1 and the core. Since a load torque acts on the metal 3, the cylindrical portion 48 of the pin 34 is rotated by the ball bearing 47 and engages with the short side 5b of the insertion hole 5.
Note that this short side 5b is the driving surface. In this case, as mentioned above, the distance S ₁ shown in Fig. 6 is the distance shown in Fig. 10.
Since the pin 34 is slightly longer than S ₂ , the pin 34 is placed in an inclined state due to the torsional deformation of the arm portion 42 of the leaf spring member 35, as shown in FIG. That is, the axis of the pin 34 has a slight inclination with respect to the vertical direction in FIG.
Due to the elastic restoring force, a biasing force in the direction of the arrow, which is the outer circumferential direction in FIGS. 8 and 10, always acts through the cylindrical portion 48 of the pin 34.

Since the core metal 3 is moved in the direction of the arrow in this way, the two sides 4a and 4b, which are farthest from the position regulating pin insertion hole 5 among the four sides of the motor shaft insertion hole 4, are crimped to the motor shaft 31a at two points. Then, the core bar 3 is positioned. Note that these two sides 4a and 4b are positioning surfaces. As a result, the center of the magnetic disk 1 attached to the core bar 3 is aligned with the motor shaft 31a.
It will be placed approximately on the axis of the In this state, the motor shaft 31a rotates and the pin 34
As the pin rotates in the direction of arrow H in FIG. is transmitted, and the core metal 3 and thus the magnetic disk 1 rotate in the direction of arrow H. At this time, as described above, the magnetic disk 1 is connected to the motor shaft 31.
Since the magnetic disk 1 is arranged concentrically with respect to a, the magnetic disk 1 is driven to rotate in a substantially centered state.

Next, the operation of the head moving device will be described. First, when the main body 20 of the apparatus is switched to, for example, the reproduction mode with the disk cassette 6 mounted as described above, the magnetic disk 1 rotates as described above. Along with this, recorded information is read out by the magnetic head 58 that is in sliding contact with the recording surface of the magnetic disk 1, and a vertical synchronization signal included in this read information is sent to a step motor drive circuit (not shown). Supplied. Each time this vertical synchronization signal is supplied, a predetermined drive current is supplied from the drive circuit to the step motor 61, and the motor shaft 61 is supplied with a predetermined drive current.
1a is rotated in the direction of arrow J in FIG. 4 by a predetermined rotation angle (for example, 15 degrees). As the motor shaft 61a rotates, the needle-shaped member 74, which is inserted without play between the threads of the feed screw 62, is fed in the direction of arrow D by the feed screw 62. As a result, the head support base 60 together with the needle-like member 74 is guided by the guide shaft 67 and moves intermittently in the direction of arrow D, that is, every rotation of the magnetic disk 1 to the next annular recording track (step Moving. Therefore, the magnetic head 58 attached to the head support base 60 and the pad support member 7
9 slide together while holding the magnetic disk 1 between them, and intermittently move inside the head and pad insertion slots 16 and 17 of the disk cassette 6 along its longitudinal direction, that is, the radial direction of the magnetic disk 1. will be moved to.

In this way, while the magnetic head 58 is in sliding contact with the magnetic disk 1, it is rotated from the outer periphery of the magnetic disk 1 to the center for each step rotation of the motor shaft 31a, that is, for each vertical synchronization signal recorded on each annular recording track. It moves in steps in the radial direction. When the head support base 60 is moved to a predetermined position and the magnetic head 58 reaches near the inner end edge of the magnetic surface of the magnetic disk 1, the position of the head support base 60 is detected by a detection mechanism (not shown) and the head is moved. movement is stopped.

Along with the above operations, information recorded on the recording surface of the magnetic disk 1 is reproduced. Note that during recording, the same operation as in the case described above is performed.

However, according to the rotary drive device configured in this way, when the core metal 3 is attracted by the magnet 52 and attracted onto the yoke 37, the position regulating pin insertion hole 5 of the core metal 3 and the position regulating pin 34 are connected to each other. 11, a part of the periphery of the upper end of the position regulating pin 34 is in contact with the long side 5a of the insertion hole 5, as shown in FIG. Pressed downward by the edges. Therefore, the position regulating pin 34 is biased by the torsional deformation of the pair of arm portions 42 of the leaf spring member 35, and rotates in this state, so that a part of the circumferential surface of the cylindrical portion 48 is pushed into the insertion hole 5. It comes into contact with the short side 5b of. If the position regulating pin 34 is not completely inserted into the insertion hole 5 and is fixed in an inclined state as described above,
The relative positional relationship between the position regulating pin 34 and the core metal 3 remains as shown in FIGS. 11 and 12, and the core metal 3 is rotated. Therefore, in this case, since the core metal 3 and thus the magnetic disk 1 are not urged in the direction of arrow I by the position regulating pin 34, the two sides 4 of the motor shaft 31a and the motor shaft insertion hole 4
a, 4b are no longer pressed into engagement. As a result, the position of the core metal 3 and, by extension, the magnetic disk 1 will not be regulated (centered) with respect to the motor shaft 31a, and there is a high possibility that a large tracking error or phase shift will occur, making recording and reproducing impossible. .

The present invention has been devised to solve the above-mentioned inconveniences, and by devising the biasing means of the position regulating pin, the position regulating pin and the rotating body can be easily attached when the rotating body is attached to the rotation drive mechanism. A rotary drive configured such that the position regulating pin is securely inserted into the position regulating pin insertion hole and the position of the rotating body is regulated with high precision, regardless of the relative positional relationship between the rotating body and the position regulating pin. The aim is to provide equipment.

Figures 13 to 15 are shown below for an embodiment of the present invention.
This will be explained with reference to the figures. In this embodiment, the leaf spring member 35, which is a means for biasing the position regulating pin 34, is improved in the rotary drive mechanism 30 described above, and the other configurations are completely the same as those described above. good. Therefore, only the configuration related to this leaf spring member will be described here. Further, in FIGS. 13 to 15, parts common to those in FIGS. 1 to 10 are given the same reference numerals, and their explanations will be omitted.

As shown in FIG. 13, the leaf spring member 35, which is the elastic member of this embodiment, is made of a single sheet metal, and includes a base plate portion 85 and a pair of arm portions 86, 87.
, a position regulating pin mounting portion 88, and a pair of L-shaped portions 89 and 90 each having a substantially L-shaped cross section. A motor shaft insertion hole 91 is formed in the substrate portion 85, and an opening 92 is formed by the substrate portion 85 and the pair of arm portions 86, 87. Further, a position regulating pin attachment portion 88 is disposed in a protruding state within this opening 92, and a position regulating pin 34 is attached to the upper surface of this attachment portion 88. Therefore, the position regulating pin 34 is disposed at a position closer to the motor shaft insertion hole 91 from the straight line connecting the pair of arm parts 86 and 87.

Furthermore, L-shaped portions 89 and 90 are integrally provided in the above-mentioned mounting portion 88 on the opposite side of the motor shaft insertion hole 91 with respect to the linear portion, and each of the L-shaped portions 89 and 90 is One piece part 89a, 90a is board part 8
It is a hanging piece that is approximately perpendicular to 5.
And each other piece part 89 of L-shaped part 89,90
b, 90b are configured substantially parallel to the substrate portion 85. Therefore, the position regulating pin 34 and the L-shaped portion 89 are aligned with the arm portion 8 with the straight line portion as the center.
The elasticity of 6,87 allows it to perform a so-called seesaw movement. As will be described in detail later, when the position regulating pin 34 is pressed downward by the core metal 3, the corner of the L-shaped member 89, that is, the point P in FIG. It becomes the center (fulcrum), but this fulcrum P is the motor shaft 3
1a and the position regulating pin 34, and the distance between the motor shaft 31a and the fulcrum P is between the motor shaft 31a and the position regulating pin 34. It is taken longer than the distance of Therefore, the position regulating pin 34 is inserted into the position regulating pin insertion hole 5 from the outer peripheral side of the position regulating pin insertion hole 5 by the plate spring member 35.
This means that it is elastically supported so that it faces the front.

Next, the operation of the rotary drive device using the above-mentioned leaf spring member 35 when a disk cassette is attached will be explained with reference to FIGS. 14 and 15.

First, the disk cassette 6 is rotated by the rotation drive mechanism 30.
If a part of the upper end of the position regulating pin 34 comes into contact with the peripheral edge of the position regulating pin insertion hole 5 of the core bar 3 when the position regulating pin 34 is attached to the is biased toward the motor shaft 31a. That is, since the position regulating pin 34 is pressed downward by the core metal 3, the pair of arm portions 86, 87 of the leaf spring member 35 are twisted and deformed due to elasticity. At this time, the position regulating pin attachment portion 88 and the L-shaped portion 89 rotate in the direction of the arrow Q in FIG. 14 about a fulcrum P, which is a corner of the L-shaped portion 89. That is, the head of the position regulating pin 34 is inclined in the inner circumferential direction and is lowered.

In this way, the upper end of the position regulating pin 34 is
Since it is biased towards the motor shaft 31a side with the point as the center of rotation, a part of the upper end surface of the position regulating pin 34 is crimped and engaged with the bottom surface 3d of the core bar 3 at one point, while other parts of this upper end surface are It will retreat downward from the bottom surface 3d. Therefore, in this case, the position regulating pin 34 does not enter the position regulating pin insertion hole 5 of the core metal 3. In this embodiment, since the L-shaped portion 90 is provided, when the position regulating pin 34 is deflected as described above, the position regulating pin 34 does not shift in the direction of arrow K (circumferential direction) in FIG. It's becoming like that.

Furthermore, since the position regulating pin 34 is rotated by the rotation drive mechanism 30, the position regulating pin 34 rotates below the core bar 3 while remaining in the above-described state. At this time, the core metal 3 and the position regulating pin 34 are crimped and engaged only at one point, and the cylindrical portion 48 of the position regulation pin 34 that is crimped and engaged with the core 3 is rotatable by a ball bearing 47. Because of this structure, the position regulating pin 3 is held against the core metal 3 which is locked by the clamping force between the magnetic head 58 and the pad 78.
4 rotates extremely smoothly.

This position regulating pin 34 is connected to the motor shaft 31.
When the position regulating pin insertion hole 5 of the core metal 3 is rotated approximately once around a, the cylindrical portion 48 of the position regulating pin 34 elastically restores the pair of arm portions 86 and 87 of the leaf spring member 35. The force causes the position regulating pin to enter the insertion hole 5 (the state shown by the imaginary line in FIG. 10). After that, position regulating pin 34
is further rotated and placed at the corner formed by the long side 5a and short side 5b of the position regulating pin insertion hole 5. As a result, as in the case of the previously described example, the position regulating pin 34 is pressed into engagement with the long side 5a as shown in FIG. It has a slight inclination with respect to the motor shaft 31a. Therefore, the core metal 3 is pressed and biased in the outer circumferential direction in FIG. 15 by the elastic restoring force of the pair of arm portions 86 and 87. As a result, the two sides 4a and 4b of the motor shaft insertion hole 4 of the core metal 3 are pressed into engagement with the motor shaft 31a at two points, thereby regulating the position (centering) of the core metal 3 and thus the magnetic disk 1. With the position regulated in this way, the core bar 3 and the magnetic disk 1 are rotationally driven by the rotational force applied from the position regulation pin 34 to the short side 5b of the position regulation pin insertion hole 5. Recording and reproducing operations are performed.

Note that even if the relative positional relationship between the position regulating pin 34 and the core bar 3 is other than the positional relationship shown in FIG. As a result, the position of the core bar 3 is regulated.

According to the rotary drive device configured in this manner, by providing the L-shaped portion 89 on the leaf spring member 35, the rotation center of the position regulating pin 34 is placed at a position far from the motor shaft 31a with respect to the position regulating pin 34. In other words, since the position regulating pin 34 was elastically supported by the plate spring member 35 so as to face the position regulating pin insertion hole 5 from the outer circumferential side of the position regulating pin insertion hole 5, any of the position regulating pins 34 Even if the part is pressed, it always tilts toward the motor shaft 31a. Therefore, there is no risk that the position regulating pin 34 will rotate the core metal 3 and eventually the magnetic disk 1 while the position regulation pin 34 remains in the state shown in FIG. No matter what the relationship is, the position regulating pin 34 is reliably inserted into the position regulating pin insertion hole 5, and as a result, the position regulation (centering) of the core bar 3 and thus the magnetic disk 1 is ensured. Moreover, it will be performed with high precision. Therefore, tracking errors and the like do not occur, and high-quality recording and reproduction can be performed.

In addition, in the present invention, since the position regulating pin 34 is provided at a position where it is crimped and engaged with the long side 5a of the position regulating pin insertion hole 5, the position regulating pin insertion hole 5
A sufficient distance is ensured between the side opposite to the long side 5a and the position regulating pin 34, and the position regulating pin 34 is placed under the side opposite to the long side 5a as in the case of FIG. There is no need to drive the short side 5b while crawling in.

Although the present invention has been described above with reference to one embodiment, the present invention is not limited to this embodiment, and various modifications can be made based on the technical idea of the present invention.

For example, the shape of the leaf spring member 35 does not necessarily have to be as shown in FIG. 13, and can be changed in various ways, and the position of the fulcrum P can be changed by changing the bending rigidity of each part of the leaf spring member. It is.

As described above, the present invention provides the rotation drive mechanism with an elastic member (for example, the leaf spring member 35) that elastically supports the position regulation pin so as to face the position regulation pin insertion hole from the outer circumferential side of the position regulation pin insertion hole. When the body (for example, the magnetic disk 1 and its core metal 3) is mounted on the rotation drive mechanism, if the position regulating pin and the position regulating pin insertion hole do not match, the head of the position regulating pin tilts toward the inner circumference. and when they are aligned, the position regulating pin is inserted into the position regulating pin insertion hole by the biasing force of the elastic member, and positioning is performed. Therefore, according to the rotary drive device of the present invention, when the rotary body is attached to the rotary drive mechanism, no matter what the relative positional relationship between the position regulating pin and the rotary body is, only a part of the position regulating pin is attached. The position regulating pin does not rotate while being inserted into the position regulating pin insertion hole, and the position regulating pin can always be reliably inserted into the insertion hole. As a result, the rotating body can always be rotated with high accuracy It becomes possible to control the position.

[Brief explanation of the drawing]

1 to 10 are for establishing a disk rotation drive device in a disk type recording/reproducing apparatus to which the present invention can be applied, FIG. 1 is an exploded perspective view of a disk cassette, and FIG. 2 is an exploded perspective view of a disk cassette. FIG. 3 is an enlarged vertical cross-sectional view of the main parts of the disk cassette with the central part of the disk cassette partially omitted, and FIG. 4 shows the above-mentioned disk cassette and this disk. An exploded perspective view showing the main body of the recording/reproducing apparatus into which a cassette is installed, FIG. 5 is an exploded perspective view of the rotational drive mechanism, FIG. 6 is a cross-sectional view taken along the line - - in FIG. 4, and FIGS. 7 and 8 are position control This is a cross-sectional view similar to Fig. 6 for explaining the operation of the pin, Fig. 9 is an exploded perspective view of the main parts of the head moving device, and Fig. 10 shows the motor shaft insertion hole of the core and its position regulation. A plan view showing a state in which the motor shaft and the position regulating pin are inserted into the pin insertion hole and the position of the core metal is regulated. FIG. FIG. 12 is a longitudinal cross-sectional view of the rotary drive device showing such a state, and FIGS. 13 to 15 show one embodiment of the present invention. FIG. 13 is a perspective view of the leaf spring member, and FIG. 14 is a rotational view showing a state in which a part of the position regulating pin is crimped and engaged with the long side edge of the position regulating pin insertion hole. FIG. 15 is a vertical cross-sectional view of the rotary drive device showing a state in which the position regulating pin is inserted into the position regulating pin insertion hole. In addition, in the symbols used in the drawings, 1...
...Magnetic disk which is a rotating body, 3... Core metal, 4...
...Motor shaft insertion hole, which is a rotating shaft insertion hole, 4a,
4b...Two sides that are positioning surfaces, 5...Position regulation pin insertion hole, 5a...Long sides that are positioning surfaces, 5
b... Short side which is a driving surface, 30... Rotation drive mechanism, 31... Motor, 31a... Motor shaft which is a rotating shaft, 34... Position regulation pin, 35... Leaf spring member which is an elastic member. 58...magnetic head,
86, 87... Arm portion, 88... Position regulating pin attachment portion, 89... L-shaped portion, P... Fulcrum.

Claims (1)

[Claims for Utility Model Registration] A disc-shaped rotating body having a rotating shaft insertion hole approximately in the center and having a position regulating pin insertion hole at a position offset from the rotating shaft insertion hole; a rotational drive mechanism each having a rotating shaft and a position regulating pin mounted in a manner capable of being deflected to a position away from the rotating shaft, the position regulating pin having a positioning surface and a driving surface; The rotating shaft is inserted into the insertion hole to urge the positioning surface toward the outer circumferential direction of the rotating body and transmit the rotational driving force of the rotational drive mechanism to the driving surface, and the rotating shaft has the positioning surface. In the rotary drive device, the rotational drive device is inserted into an insertion hole and is pressed into engagement with the positioning surface by the biasing force of the position regulating pin, thereby positioning the rotating body with respect to the rotating shaft. The rotary drive mechanism is provided with an elastic member that elastically supports the regulating pin so as to face the position regulating pin insertion hole from the outer circumferential side of the position regulating pin insertion hole, and when the rotating body is mounted on the rotary drive mechanism. When the position regulating pin and the position regulating pin insertion hole do not match, the head of the position regulating pin tilts toward the inner circumference and descends, and when they match, the position regulating pin is pressed by the biasing force of the elastic member. A rotary drive device characterized in that the positioning pin is inserted into the position regulating pin insertion hole to perform positioning.