JP2921171B2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus such as a helical video tape recorder having a rotary cylinder having a plurality of magnetic heads.

[0002]

2. Description of the Related Art In recent years, magnetic recording / reproducing devices such as cassette type video tape recorders have been reduced in size and weight. A mechanism using a small-diameter cylinder with four heads and a set wrap angle of 285 ° is becoming mainstream.

Hereinafter, the configuration of a conventional magnetic recording / reproducing apparatus will be described with reference to FIGS.

FIG. 11 is a plan view of a conventional magnetic recording / reproducing apparatus. In the figure, 101 is a cassette containing a reel on which a magnetic tape is wound, and 102 is a magnetic head 103
This is a rotary cylinder in which a to 103d are arranged at 90 ° intervals on the circumference. 104a and 104b are tape guide posts, which are arranged in the cassette opening (shown by broken lines) when a cassette is mounted, and when the cassette detection switch (not shown) detects the cassette mounting, the tape guide posts 104a and 104b are arrows. The tape is loaded along the path indicated by, and is fixed at a predetermined position. 105a, 10
5b is an inclined post, and the inclined post 105a is fixed to the same substrate as the tape guide post 104a.
The inclined post 105b is fixed on the substrate 109. Reference numeral 106 denotes a capstan for moving the magnetic tape 110 at a predetermined speed. The capstan 106 presses the magnetic tape 110 against the capstan 106 by a pinch roller 108 to transmit the rotational force of the capstan 106 to the magnetic tape 110. Is transported at a predetermined speed.

Next, in order to reduce the size of the magnetic recording / reproducing apparatus,
There is a first substrate on which a rotary cylinder is mounted, and a second substrate for holding a cassette, and the second substrate slides toward the rotary cylinder of the first substrate during loading. The mechanism will be described.

As shown in FIG. 13, a rotary cylinder 111 and first to sixth gears (116 to 12) are provided on a first substrate 112.
1), a mode switch 122, a cam gear 123 and an arm 127 are attached. An elongated hole 114 on the second substrate 113 is guided by a guide shaft 115 erected on the first substrate 112, and the second substrate 113 is
14 so that it can slide along.

In FIG. 13, when a first gear 116 is driven by a loading motor (not shown), a driving force is generated by a gear train including first to sixth gears (116 to 121), a mode switch 122 and a cam gear 123. Is transmitted to the cam gear 123 to rotate the cam gear. Then, since the pin 126 attached to the arm 127 moves along the cam groove 124, the arm 127 rotates counterclockwise about the arm shaft 125, and the pin 129 at the tip of the arm is rotated.
And the groove 128 on the second substrate, the second substrate 113 moves along the elongated hole 114 in the direction of the rotary cylinder 111 on the first substrate 112. FIG. 14 shows a state in which the movement of the second substrate 113 has been completed.

[0008]

However, there is provided a first substrate on which the rotary cylinder is mounted, and a second substrate which holds the cassette and slides in the direction of the rotary cylinder. The mechanism that is reduced in size by moving the second substrate in the direction of the rotary cylinder has a problem that the number of components increases due to the complexity of the mechanism configuration, and it is difficult to reduce the size and weight. Was.

An object of the present invention is to solve the above-mentioned problems and to provide a magnetic recording / reproducing apparatus which can reduce the number of parts and realize a reduction in size and weight of the apparatus.

[0010]

To achieve the above object, a magnetic recording / reproducing apparatus according to the present invention comprises a rotating cylinder, a first substrate to which the rotating cylinder is mounted, and a magnetic tape from a magnetic tape cassette to the outside of the cassette. A post wound around the drawer rotary cylinder over a predetermined angle, and a second substrate that moves in the direction of the rotary cylinder while holding the cassette while performing the operation of winding the magnetic tape around the rotary cylinder at a predetermined angle; and internal gear formed on the first substrate, and a planetary gear provided with an eccentric pin at a position revolved eccentrically while meshing with the internal gear, a sun gear located at the center of the internal gear meshing with the planetary gear, the sun driving means for imparting a rotational force to the gear, it is formed on a second substrate, a cam groove configured to guide the eccentric pin, the planetary teeth
Engage with the eccentric pin provided on the vehicle and drive with the eccentric pin.
A pinch for moving and pressing a pinch roller against the magnetic tape
A crimping mechanism and the planetary gear arranged coaxially with the internal gear and
It has a pin that engages with a hole provided in the
A mode switch that rotates in synchronization with the
Device operation status can be detected by switch contact
A printed circuit board having a flexible foil, and provided on the planetary gear.
When the eccentric pin draws the first cycloid curve,
The second substrate moves in the direction of the rotary cylinder,
After the eccentric pin draws the second cycloid curve before
Operate the pinch crimping mechanism to pinch the magnetic tape.
Switch to press the roller, and further the planetary gear
The mode switch and the switch that rotate in synchronization with the revolution of
Operation of the device by contact with the foil provided on the lint board
The state is detected.

[0011]

According to the present invention, the eccentric pin provided on the planetary gear draws a cycloid curve, and when the first cycloid curve is drawn, the second substrate moves in the direction of the rotary cylinder. While the curve is being drawn, the operation mode of the device such as pinch roller pressing is switched. Since the mode switch is arranged coaxially with the sun gear and is arranged to rotate in synchronization with the revolution of the planetary gear, the operation switching mechanism and the mode switch can be stored in the space of the internal gear, and the number of parts can be reduced. Reduction and large space saving can be realized.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic recording / reproducing apparatus according to one embodiment of the present invention will be described below with reference to the drawings.

First, the tape loading means will be described (see FIGS. 1 and 2). FIG. 1 is a schematic plan view showing the configuration of a magnetic recording apparatus according to one embodiment of the present invention, and FIG. 2 is a plan view of a loading mechanism using a post holder during loading of the apparatus. In the figure, 2 is a rotary cylinder,
A magnetic tape 14 drawn from a cassette 1 mounted on a magnetic recording / reproducing apparatus is wound around an outer peripheral surface in an M-shape.
This rotary cylinder 2 has a set of four magnetic heads 3a,
3b, 3c and 3d have their tips slightly projecting to the outer periphery of the cylinder, and are arranged on the circumference at 90 ° intervals. A loading ring 4 for guiding the magnetic tape 14 drawn from the cassette 1 around the outer peripheral surface of the rotating cylinder 2 is provided around the outer periphery of the rotating cylinder 2 with a ring roller 9.
It is provided so that it can rotate. When the tape loading is completed via the rotatably provided rod 7, the loading ring 4 includes a second post 5 b and a tape guide post 6 d which are inclined posts fixed in parallel with the rotary cylinder 2. A second post holder 8b for holding is provided. The loading ring 4 includes a rack gear 13 a provided on the second substrate 16.
As a result, it is turned through the transmission gear 13b. The second post holder 8b operates to wind the magnetic tape 14 wrapped around the second post 5b and the tape guide post 6d around the rotary cylinder 2 from the counterclockwise direction along the loading guide T33. Reference numeral 8a denotes a first post holder which holds the first post 5a and the tape guide post 6c, which are inclined posts fixed parallel to the rotary cylinder 2 when the tape loading is completed. The first gear 36 is provided on the first substrate 15.
Is a loading guide S provided with: Reference numeral 40 denotes a loading plate which moves on the surface of the first substrate 15 in both directions of arrows A and B (FIG. 2), and a rotation shaft 38 of a second gear 37 meshing with the first gear 36; The roller 15 includes a roller 39 that is in contact with the inner surface 15 ′ of the roller 15 and a connecting shaft 41 that is connected to the second substrate 16.
Reference numeral 42 denotes a U-shaped member, which is a second loading arm mounted on the loading plate 40 so as to be freely rotatable about the rotation shaft 38. The second loading arm 42 is provided with an arm portion and a third gear 43 meshing with the second gear 37, and the first post holder 8a
Axis 44 of the first loading arm 35 supporting the
Is set up.

Reference numeral 45 denotes a fourth gear, to which a force in one direction is constantly applied by a compression spring 46. Fourth gear 4
5 engages with the second gear 37 as the loading plate 40 moves in the direction of arrow A, and when the tape loading is completed and the post holder 8a is fixed at a predetermined position, the second gear 37 is integrated with the second gear 37. , And slides in the direction of arrow A.

Next, a mechanism for pulling out the tape guide post 6f will be described (see FIGS. 1, 2 and 3).

A tape guide post arm 25 having a rotation fulcrum 26 is mounted on the second substrate 16, and the tape guide post arm 25 is attached to the first substrate 15.
A cam pin 28 is provided corresponding to a guide groove 27 'formed by the guide 27 provided in the first and second springs.

Next, the tension regulator mechanism will be described with reference to FIG. On the second substrate 16, a tension post 21 for detecting a tape tension at the time of recording / reproducing and maintaining a constant tension is held.
A tension arm 22 is provided which can rotate around the center. A tension band 23 wound around a brake drum 17 a formed on the reel base 17 and applying a braking force to the reel base 17 is applied to the tension arm 22. Reference numeral 30 shown in FIG. 1 denotes a tension post release cam fixed to the first substrate 15, which cam portion 30a releases the tension arm 22 during loading and unloading, and prevents the return of the tension arm 22 during REV and REW. And a cam portion 30b.

Next, a description will be given of the cassette mounting portion and the means for moving the cassette into and out of the cabinet.

On the side facing the rotary cylinder 2, a cassette mounting portion for mounting the cassette 1 is formed. The cassette mounting portion places the mounted cassette 1 in the opening of the cassette 1. A cassette holder is provided which is held on the second substrate 16 (FIG. 3) which moves so as to be accommodated, and which operates to raise and return the tape cassette 1 mounted at the time of ejection to the cassette insertion / ejection side of the apparatus main body. ing. A pair of reel stands 17 and 18 are provided on the second substrate 16. The cassette 1 has a magnetic tape 14 wound thereon. The reel base 1 corresponding to the tape supply reel 19 and the tape take-up reel 20, respectively.
It is fitted to 7,18. The second substrate 16 has elongated holes 16 a to 16 b corresponding to the guide pins provided on the first substrate 15.

Next, a switching mechanism using a planetary gear will be described. In FIG. 1, an internal gear 20 is provided on a first substrate 15.
1, a sun gear 202 is provided at the center thereof, and a fifth gear 2 is provided by a loading motor (not shown).
09 (FIG. 11) drives the integrated sun gear 202. Reference numeral 203 denotes a planetary gear which revolves while engaging with the internal gear 201 and the sun gear 202, and an eccentric pin 204 is set up at an eccentric position.
This eccentric pin 204 is associated with a cam groove 61 formed on the second substrate 16, and its curve matches the second cycloid curve 208 drawn by the eccentric pin 204.

Next, a pinch roller pressing mechanism will be described with reference to FIGS.
This will be described with reference to FIG. An eccentric pin 204 set at an eccentric position of the planetary gear 203 is connected to move a rod 205. A pinch roller pressing spring 57 is attached to the rod 205 by the spring holding plate 20.
6 attached. In FIG. 6, reference numeral 51 denotes a pinch arm having a rotating shaft 53 vertically set on the first substrate 15 as a support shaft. The pinch roller 47 is rotatably mounted on a tilted pinch roller shaft 52 so that the pinch roller 47 can be accommodated in the cassette opening during unloading. The pinch roller shaft 52 connects the pinch roller 47 to the capstan 48. When pressed, it becomes parallel to the capstan 48. Spring holding plate 206
Is connected to a toggle mechanism including a pinch roller pressure lever 54 and a pinch roller pressure lever 55, and is configured such that when the rod 205 is pulled to the left, the pinch roller pressure operation is performed by the toggle mechanism.

Next, the mode switch will be described (FIGS. 1, 10 and 11). The mode switch 210 is rotatably arranged coaxially with the sun gear 202, and the planetary gear 203 rotates around the projection 211 at an eccentric position on the mode switch 210. Therefore, the mode switch 210 rotates according to the revolution of the planetary gear 203.
A conductive brush 212 serving as an electrical contact is attached to the mode switch 210.
When the brush 212 is brought to a predetermined position by rotating 0, it is configured to contact the foils 214 and 215 on the flexible printed board 213, and the foils 214 and 215 detect a circuit operation state (not shown). To detect the operating state of the device.

Next, the tape path will be described (FIGS. 1 and 4). In the figure, the magnetic tape 14 pulled out from the tape supply reel 19 is transferred to the cassette 1 from the cassette 1 through the tape guide post 6a, the tension post 21, the tape guide posts 6b and 6c, and to the first post 5a. Pulled out horizontally. The first post 5 a and the second post 5 b pull out the magnetic tape 14 from the opening of the cassette 1 and
It is fixed above and is arranged in parallel with the axial direction of the rotary cylinder 2. Magnetic tape 1 wound around rotating cylinder 2
4 descends along the lead surface formed on the rotary cylinder 2, and the second post 5b and the tape guide post 6d
After that, it gradually rises, travels at a constant speed by the capstan 48 and the pinch roller 47, and reaches the tape guide post 6e. At the position of the tape guide post 6e, the magnetic tape 14 is fed to the tape supply (take-up) reel 19 (2).
It has returned to the height of 0). After that, the third post 5c provided to be inclined with respect to the magnetic tape 14,
The twist of the magnetic tape 14 is eliminated, and the magnetic tape 14 is configured to be wound on the tape winding reel 20 via the tape guide post 6f.

Next, when the tape loading is completed, the first post 5 fixed parallel to the rotary cylinder 2 is used.
The method for fixing the second post 5a and the second post 5b will be described with reference to FIG. FIG. 5 shows the first post 5a and the second post 5a.
FIG. 9 is a schematic plan view showing the arrangement of stopper pins 49 for accurately fixing the post 5b at a predetermined position.
(Note that FIG. 9 is a perspective view of the first substrate 15 provided with the stopper pins 49 for reference.) In FIG. 5, the stopper pins 49 are provided on the first substrate 15 on the cylindrical surface of the rotary cylinder 2. It is set up in parallel with the central axis of. The first post 5a and the second post 5b attached to the post holders 8a and 8b include a cylindrical portion of the lower cylinder 50 (having a diameter larger than the cylinder diameter by a step difference forming a lead) and a stopper pin 49. Therefore, it is fixed so as to be sandwiched.

With this configuration, the positional accuracy of the first post 5a and the second post 5b with respect to the rotary cylinder 2 in a plan view can both be brought into contact with the cylindrical portion of the lower cylinder 50 of the rotary cylinder 2 and the lower cylinder 50 Since the stopper pins 49 are set up vertically on the first substrate 15 to be mounted, high-precision positioning is possible.

The operation of the magnetic recording / reproducing apparatus configured as described above will be described below. FIG. 7 is a plan view showing a state where the cassette mounting device has been moved out of the cabinet.
In this state, the conductive brushes 212 attached to the mode switch 210 shown in FIG.
15a is connected to detect an unloading state. First, as shown by the dashed line, when the cassette 1 is mounted on the apparatus, the cassette mounting is detected by a detection switch (not shown) for detecting the cassette mounting, and the sun gear 202 is rotated counterclockwise by the loading motor (not shown). As a result, the planetary gear 203 rotates clockwise,
Revolves around sun gear 202. The eccentric pin 204 provided on the planetary gear 203 has the first cycloid curve 20.
Draw 7. Thus, the second eccentric pin 204 corresponding to the second
The cam groove provided on the second substrate 16 allows the second substrate 16
Moves along the slots 16a, 16b, 16c, 16d (FIG. 3) in the direction of the rotary cylinder 2, and the rack gears 13a,
The driving force is transmitted to the loading ring via the transmission gear 13b, and the magnetic tape 14 housed in the opening of the cassette 1 is fixed to a predetermined position outside the cassette 1 by the tape guide post 6d provided in the second post holder 8d. Pulled out to the position (FIG. 1) and locked by the fixing means.

Next, the tape loading operation by the first post holder 8a will be described with reference to FIGS. 1, 2, 7 and 8.

When the second substrate 16 is moved toward the rotary cylinder 2,
The loading plate 40 moves integrally with the moving operation. With this movement, the second gear 37 installed on the loading plate 40 is rotated clockwise by the first gear 36, and the first loading having the third gear 43 meshing with the second gear 37. The arm 35 is rotated counterclockwise. By these operations, the first post holder 8a is moved so as to pull out the magnetic tape 14 from the inside of the opening of the cassette 1 to the outside of the cassette. In addition, the first post 5a provided on the first post holder 8a causes the movement trajectory of the tape guide post 6c to follow the loading guide 34, and the one end 35 'of the first loading arm 35 to be rotated as described above. By performing the moving operation, it is moved to the position shown in FIG.

By this operation, the distance between the first post 5a and the rotary cylinder 2 during the loading can be sufficiently ensured, and the first post 5a is brought close to the rotary cylinder 2 immediately before the loading is completed. Can be realized.

The rotation shaft 4 of the first loading arm 35 provided on the second loading arm 42
4 is a rotation preventing guide 62 during the loading operation.
Thus, the rotation around the rotation shaft 38 is restricted, and the rotation restriction is released when the first post holder 8a moves to the position shown in FIG. With the above configuration, the variation in the distance between the one end 35 'of the first loading arm 35 and the rotation shaft 38 when the first post holder 8a is pressed against the first post holder 8a is reduced by the second loading arm 42 and the first loading arm 35a.
And the rotation shaft 38, the first loading arm 35
Of the tape guide post 6c with the stopper 63.
It generates a force to press. At the time of pressure bonding, the first and second loading arms 35 and 42 operate substantially integrally. Further, the pressing force of the first post holder 8a is generated by the pressing spring 46.

Next, the operation of pulling out the tape guide post 65 will be described. Tape guide post 6f (Fig. 1,
Tape guide post arm 25 holding FIGS. 3 and 7)
Is mounted on the second substrate 16, and the tape guide post arm 25 is rotated clockwise as the second substrate 16 moves toward the rotary cylinder 2 from the state shown in FIG. 7. You.

When the movement of the second substrate 16 is completed, the tape guide post 6f hits the stopper 64 provided on the first substrate 15, and the urging force of the leaf spring 65 acts on the cam pin 28. It is configured as follows. The stopper 64 has a surface 64 ′ parallel to the magnetic tape 14 drawn out from the third post 5 c. A portion 2 formed concentrically with the center of the tape guide post 6f of the tape guide post arm 25 on the parallel surface 64 '.
5 ′ (FIG. 1), even if the stop position of the second substrate 16 fluctuates, the third
The winding angle of the magnetic tape 14 around the post (inclined post) 5c can be kept constant.

When the cassette 1 moves to a predetermined position (FIG. 1), the foils 214 and 215b are connected by the brush 212 (FIG. 11) attached to the mode switch 210, and the state of the completion of the movement of the second substrate is determined. To detect. afterwards,
The eccentric pin 204 moves along the cam groove 61. At this time, since the cam groove 61 matches the locus of the eccentric pin 204 on the second cycloid curve 208, the second substrate 16
Has stopped.

Next, the pinch roller pressing operation will be described (FIG. 1). When the tape loading is completed and the loading motor (not shown) continues to rotate, the eccentric pins 204 provided on the planetary gear 203 move to the second substrate 1.
It moves along the cam groove 61 provided on the reference numeral 06. This cam groove matches the second cycloid curve generated by the eccentric pin 204. In addition, while the second substrate 16 is moving, the eccentric pin 204 draws the first cycloid curve, but the rod 205 is set at a position where the rod 205 only makes a pivoting motion and does not perform a pinch crimping operation. When the eccentric pin 204 reaches the second cycloid curve 208, the rod 205 is pulled only for the first time.
At this time, the pinch crimp spring 5
7 is pulled, and a pinch roller 47 is
The spring holding plate 206 is moved to the left so that is pressed. With the above configuration, the magnetic tape 14
Can be moved at a predetermined speed.

When the eccentric pin 204 comes to the lower left end position of the second cycloid curve 208, the foil 214 and 215C are connected by the brush 212 attached to the mode switch 210 in FIG. When the completion of all the switching operations by the planetary gear mechanism such as the crimping operation is detected, the device becomes operable.

As described above, according to the magnetic recording / reproducing apparatus of the embodiment of the present invention, the eccentric pin is provided on the planetary gear that moves around the sun gear provided on the first substrate, and the operating state of the mechanical unit is controlled by the pin. , And a switch for informing the electric section of the operation mode is provided, so that the device can be reduced in size and weight.

[0037]

As is apparent from the above embodiments, according to the present invention, the first substrate on which the rotary cylinder is mounted and the guide post perform the operation of winding the rotary cylinder at a predetermined angle and simultaneously hold the cassette. A second substrate moving in the direction of the rotary cylinder, an internal gear formed on the first substrate, a planetary gear provided with an eccentric pin at an eccentric position revolved while engaging with the internal gear, and a planetary gear A sun gear located at the center of the meshing internal gear, driving means for applying a rotational force to the sun gear, a cam groove formed on the second substrate along the eccentric pin, and a rotary cylinder of the second substrate After the movement in the direction is completed, means for switching the operation mode of the device such as a pinch roller press, and a mode switch arranged coaxially with the internal gear and rotated in synchronization with the revolution of the planetary gear are provided. It has. Therefore, since the planetary gear mechanism itself forms a speed reduction mechanism, it has both an operation switching function and a speed reduction function, and the mode switch is arranged coaxially with the sun gear, which is advantageous for miniaturization. Further, since the second substrate and the planetary gears can be arranged close to each other, a resistance against external force is received by the short eccentric pin, so that a strong structure can be obtained. Further, in the vicinity of the transition from the first cycloid curve to the second cycloid curve, the moving speed of the eccentric pin is inevitably slowed, so that the moving force of the second substrate is large and the fixing force of the tape guide post is sufficiently increased. A magnetic recording / reproducing apparatus having many features that it can be ensured can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a magnetic recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a loading mechanism using a first post holder during loading of the apparatus.

FIG. 3 is a plan view showing a configuration of a second substrate of the apparatus.

FIG. 4 is a perspective view showing a tape path of the apparatus.

FIG. 5 is a plan view showing a method of fixing a first post and a second post of the device.

FIG. 6 is a side view of a pinch roller pressing arm of the apparatus.

FIG. 7 is a plan view of the apparatus at an unloading position.

FIG. 8 is a plan view of a loading mechanism using a first post holder during unloading of the apparatus.

FIG. 9 is a perspective view of a first substrate of the apparatus.

FIG. 10 is a sectional view of a planetary gear switching mechanism and a mode switch of the present invention.

FIG. 11 is a plan view of a mode switch of the present invention.

FIG. 12 is a schematic plan view of a conventional magnetic recording / reproducing apparatus.

FIG. 13 is a plan view of a conventional magnetic recording / reproducing apparatus during unloading.

FIG. 14 is a plan view of a conventional magnetic recording / reproducing apparatus during loading.

[Explanation of symbols]

 2 Rotating cylinder 5a First post (inclined post) 5b Second post (inclined post) 15 First substrate 16 Second substrate 54 Pinch crimp lever 55 Pinch crimp lever 61 Cam groove 201 Internal gear 202 Sun gear 203 Planet Gear 204 Eccentric pin 205 Rod 206 Spring holding plate 210 Mode switch 212 Brush 213 Flexible printed circuit board 214 Foil 215 Foil

Claims (1)

(57) [Claims] 1. A rotary cylinder having a magnetic head, a first substrate to which the rotary cylinder is attached, and a post which pulls out the magnetic tape from a magnetic tape cassette to the outside of the cassette and winds the magnetic tape around the rotary cylinder at a predetermined angle. A second substrate that moves the direction of the rotating cylinder, while the post performs an operation of winding the magnetic tape around the rotating cylinder at a predetermined angle, and holds the cassette; A formed internal gear,
A planetary gear provided with an eccentric pin at an eccentric position that revolves while engaging with the internal gear, a sun gear meshing with the planetary gear and a sun gear located at the center of the internal gear, and a driving unit that applies a rotational force to the sun gear; A cam groove formed on the second substrate and configured to guide the eccentric pin;
The eccentric pin engages with an eccentric pin provided on the planetary gear, and
And a pinch roller is pressed against the magnetic tape.
Pinch crimping mechanism, and whether it is arranged coaxially with the internal gear
A pin that engages with a hole provided in the center of rotation of the planetary gear.
A mode switch which rotates in synchronism with the revolution has down, before
The operation status of the device by touching the mode switch
And a printed circuit board having a foil capable of detecting the eccentricity. When the eccentric pin provided on the planetary gear draws a first cycloidal curve, the second substrate moves in the direction of the rotary cylinder, and then the eccentricity When the pin draws a second cycloidal curve, the pinch crimping mechanism is operated to activate the magnetic tape.
And a mode switch which rotates in synchronization with the revolution of the planetary gear.
A magnetic recording / reproducing apparatus configured to detect an operating state of the apparatus by contact between the switch and a foil provided on the printed circuit board .