JPH0633554Y2 - Reel shaft drive mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a reel shaft drive mechanism that can be suitably implemented in an audio device such as a vehicle-mounted cassette tape recorder.

2. Description of the Related Art FIG. 8 is a perspective view showing a schematic configuration of a typical prior art. A pulley 3 is fixed to the output shaft 2 of the drive motor 1, and an endless belt 5 is wound and stretched around the pulley 3 and the left flywheel 4a. The right flywheel 4b is attached to the belt 5 stretched between the pulley 3 and the left flywheel 4a.
Are in contact with each other, and the guide rollers 6 keep the surfaces of the belt 5 facing each other apart from each other so as not to contact each other. Shafts 7a and 7b are inserted into and fixed to the flywheels 4a and 4b, respectively. First drive gears 8a, 8b and second drive gears 9a, 9b having a smaller diameter than the first drive gears 8a, 8b are coaxially fixed to the shafts 7a, 7b. Therefore, when drive power is supplied to the drive motor 1, the output shaft 2 is rotationally driven around its rotation axis, and accordingly, the pulley 3 is rotationally driven and the belt 5 is rotated.
Is driven in the direction of arrow A1. As a result, each flywheel 4a, 4b has an arrow around the axis of rotation of the shaft 7a, 7b.
It is driven to rotate in the directions of 10a, 10b, respectively, so that the first drive gears 8a, 8b and the second drive gears 9a, 9b are connected to the shafts 7a, 7b.
Rotation direction of each flywheel 4a, 4b around the rotation axis of b
It is rotationally driven in the same direction as 10a and 10b.

The rotational force of the right flywheel 4b that is rotationally driven in this way is transmitted through the first drive gear 8b and the second drive gear 9b,
Recording / reproducing idler gear 11 meshing with the second drive gear 9b
The take-up reel 12b is transmitted via b to the reel driving gear 14b mounted by the shaft 13b.

Further, the rotational force of the left flywheel 4a is transferred to the recording / reproducing idler gear 11 via the first drive gear 8a and the second drive gear 9a.
The rotational force of the recording / reproducing idler gear 11a is transmitted to the reel gear 14a that rotationally drives the shaft 13a to which the take-up reel 12a is attached.

Furthermore, when winding the tape of the magnetic tape cassette mounted on the take-up reels 12a, 12b to either the left or right side,
The recording / reproducing idler gears 11a and 11b are the second drive gears 9
The idler gear for rapid traverse is separated from a and 9b.
15 meshes with the first drive gear 8a and the reel gear 14a, or the first drive gear 8b and the reel gear 14b, so that either the take-up reel 12a or the take-up reel 12b is rotationally driven.

In such a prior art, for example, the take-up reel 12a, 12b with the magnetic tape cassette mounted is
When the magnetic tape winding operation is performed by rotating 12b, a load acts on the take-up reel 12b. This way take-up reel 12b
The load on the reel gear is non-uniform depending on the winding state of the magnetic tape, and therefore the load on the reel gear is affected by such load.
There is a variation in the rotation speed of 14b, which prevents the shaft 7b from rotating at a constant rotation speed. When the rotation speed of the shaft 7b varies in this way, the pinch roller 16
The magnetic tape interposed between b and the shaft 7b cannot be driven and driven at a constant speed, which deteriorates the so-called wow-flatter performance, which deteriorates the sound quality during playback and recording. , Can not record and play with good sound quality.

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to prevent the variation of the running speed of the magnetic tape without increasing the size of the device, and to enable recording / playback with good sound quality. To provide a reel shaft drive mechanism.

According to the present invention, a left drive gear and a right drive gear, which are rotationally driven in opposite directions to each other, and a left and right drive gears, are rotationally driven in the same direction as the respective rotational directions of the drive gears, and the reel shaft is projected. A left transmission gear and a right reel gear that are provided, and a power transmission mechanism that is interposed between the left and right drive gears and the left and right reel gears. The first gear that has the same diameter and always meshes with each other. And a second gear, and coaxially fixed to a common side of the first gear and the second gear, respectively, and having a third gear and a fourth gear having a smaller diameter than the first gear and the second gear, the first gear The gear and the second gear are configured to be angularly displaceable around a position that is equidistant from each rotation center, and either the first gear or the second gear meshes with the corresponding left drive gear or right drive gear. When engaged, the first gear or the first gear The power is transmitted to the corresponding left or right reel gear by the third gear or the fourth gear fixed to either of the two gears, respectively, and the power transmitted to the left reel gear or the right reel gear is switched. At this time, the reel shaft drive mechanism is characterized by including such a power transmission mechanism that is driven to perform the angular displacement around the equidistant position.

Further, the present invention is for a left reel in which a left drive gear and a right drive gear, which are rotationally driven in opposite directions to each other, and a left drive gear and a left drive gear, respectively, are rotationally driven in the same directions as the respective rotation directions of the left and right drive gears, and a reel shaft is projectingly provided. A power transmission mechanism interposed between a gear, a right reel gear, and left and right drive gears and left and right reel gears, which are rotationally driven by meshing with either the left drive gear or the right drive gear. A first gear, a second gear having a smaller diameter than the first gear, a third gear rotationally driven by the second gear, and a third gear coaxially formed with the first gear. , A fourth gear having a smaller diameter than the third gear, and a fifth gear that is rotationally driven by the fourth gear, wherein the rotation axes of the first gear, the second gear, and the fifth gear are the first gear. When equidistant from the rotation axes of the third gear and the fourth gear, And a fourth gear configured to be angularly displaceable about a rotation axis of the fourth gear, and when the first gear meshes with one of the left and right drive gears, the fifth gear has either the left or the right. Power is transmitted by meshing with the other reel gear, and when the left reel gear and the right reel gear are switched, the angular displacement is driven around the rotation axes of the third gear and the fourth gear. A reel shaft drive mechanism including such a power transmission mechanism.

According to the present invention, when the first gear and the second gear mesh with either the left drive gear or the right drive gear, either the fourth gear or the third gear is used for the other reel. Power is transmitted to the gears, the power transmission mechanism is angularly displaced, and the take-up reel is switched to either left or right. Thus, even if a load is applied to the take-up reel by winding the magnetic tape or the like, the rotation of the take-up reel is applied to the drive gear on the side where the tape does not come into contact via the power transmission mechanism. Therefore, recording / playback can be performed with good sound quality without causing variations in the running speed of the magnetic tape.

Embodiment FIG. 1 is a plan view showing the basic construction of an embodiment of the present invention, FIG. 2 is a sectional view thereof, and FIG. 3 is an exploded perspective view thereof. For example, a drive motor 22 is fixed to a chassis 21 of a magnetic tape recording / reproducing device 20 such as an on-vehicle magnetic tape cassette recorder, and an output shaft 23 of the drive motor 22 is fixed.
A pulley 24 is fixed to the. An endless belt 26 is wound around and stretched around the pulley 24 and the left flywheel 25a. The right flywheel 25b comes into contact with the belt 26, and the guide rollers 27 keep the mutually facing surfaces of the belt 26 separated from each other. Axis 28 on flywheels 25a, 25b
a and 28b are fixed respectively, and the left drive gear 29a and the right drive gear 29b are coaxially fixed to the shafts 28a and 28b, respectively. axis
Pinch rollers 30a and 3 that come into contact with and separate from 28a and 28b, respectively
0b is provided rotatably around an axis parallel to the axes of the shafts 28a, 28b. When drive power is supplied to the drive motor 22, the output shaft 23 is rotationally driven around its rotation axis, and thus the pulley 24 is rotationally driven and the belt 26 is driven to travel in the direction of arrow B1. . Thereby, the flywheels 25a and 25b are rotationally driven in the directions of the arrows 31a and 31b, respectively.
Therefore, the drive gears 29a and 29b are rotationally driven in the same direction.

The rotation of the flywheels 25a and 25b is transmitted to the shafts 28a and 28b, and one of the pinch rollers 30a and 30b comes into contact with the shafts 28a and 28b and is driven to rotate. When the magnetic tape 33 of the magnetic tape cassette 32 indicated by the phantom line in FIG. 1 is driven to run toward the arrow C1, the pinch rollers 30a and 30b come close to the shaft 28a. The magnetic tape 33 is pinched by the shaft 28a and the pinch roller 30a by being displaced in the direction. Also magnetic tape
When 33 is driven to travel in the direction of arrow C2, the other pinch roller 30b is displaced in the direction of approaching the shaft 28b and the shaft 28b
The magnetic tape 33 is sandwiched between b and the pinch roller 30b. In this state, the magnetic tape 33 shows the arrow C1.
Heading or arrow C2
Is displaced to a position shown by an imaginary line 35 in FIG. 1 and the magnetic tape 33 contacts the head 34. In such a state, the storage / reproduction operation of the magnetic tape 33 is performed.

The drive gears 29a, 29b include fast-forward idler gears 36a, 3
6b mesh. The fast-forward idler gear 36a is attached to a swing arm 38a whose base end is pivotally supported by a shaft 37a so as to be angularly displaceable around the axis, whereby the fast-forward idler gear 36a is driven by a drive gear. It can be displaced in the direction of approaching / separating from 29a. Such a fast-forward idler gear 36a is rotatable about its axis by the shaft 39a. When the fast forward idler gear 36a is angularly displaced in the direction of approaching the drive gear 29a, the fast forward idler gear 36a
36a meshes with the drive gear 29a and the shaft 4 of the reel 40a
It meshes with the reel gear 42a fixed to 1a. Therefore, the rotational force of the flywheel 25a is 3
It is transmitted to the reel gear 42a via 6a, whereby the reel 40a is rotationally driven via the shaft 41a. In the state where such a fast-forward idler gear 36a meshes with the drive gear 29a and the reel gear 42a, the head 34 is attached to the magnetic tape 3a.
It has returned to the initial position separated from 3, and the pinch roller 30
The a and 30b are separated from the shafts 28a and 28b.

FIG. 4 is a perspective view of the recording / reproducing idler gear train 45. A recording / reproducing idler gear train 45 for realizing a power transmission mechanism is interposed between the drive gears 29a, 29b and the reel gears 42a, 42b. Recording / playback idler gear train 45
Are coaxially formed on the common side of the first gear 46 and the second gear 47, which have the same diameter and always mesh with each other, and the common sides of the first and second gears 46, 47, respectively. A third gear 48 and a fourth gear 49 having a smaller diameter than 47 are included. With the first gear 46 and the third gear 48, and the second gear 47 and the fourth gear 49 arranged coaxially, respectively, the shaft 50 and
51 is inserted, and the shafts 50 and 51 are connected by a connecting member 52 formed in a substantially T shape, whereby the first gear 46 and the second gear 47 are always in mesh with each other. .

A fitting hole 54 is formed at an intermediate position between the shaft 50 and the shaft 51 of the connecting member 52, into which a support shaft 53 protruding from an upper plate 21a arranged above the chassis 21 is fitted. Fitting hole of connecting member 52
When the support shaft 53 is fitted in the support shaft 54, the recording / reproducing idler gear train 45 is angularly displaceable around the axis of the support shaft 53.

A swing lever 56 is connected to the connecting member 52 by a pin 55. As the swing lever 56 moves in the direction of arrow D1 in FIG. 1, the connecting member 52 is angularly displaced around the axis of the support shaft 53, and the first gear 46 meshes with the drive gear 29a. , The fourth gear 49 meshes with the reel gear 42b.

Next, the operation of the magnetic tape recording / reproducing apparatus 20 will be described. When drive power is supplied to the drive motor 22, the output shaft
23 is driven to rotate about its rotation axis, and therefore the pulley 24 fixed to the output shaft 23 is driven to rotate in the same direction. As a result, the belt 26 is driven and driven in the arrow B1 direction, and the flywheels 25a and 25b are rotationally driven in the arrow 31a and 31b directions, respectively. When the flywheels 25a and 25b are rotationally driven, the drive gears 29a and 9b are driven in the same directions as the arrow 31a and 31b directions, respectively.

In such a state, when the swing lever 56 is displaced in the direction of arrow D1 and the connecting member 52 is angularly displaced around the axis of the support shaft 53, the first gear 46 meshes with the drive gear 29b and the drive gear 29a. Is transmitted to the first gear 46. The rotation of the first gear 46 is the second
The fourth gear 49, which is transmitted to the gear 47 and is fixed coaxially with the second gear 47, is rotationally driven in the same direction. The rotation of the fourth gear 49 is transmitted to the reel gear 42b, so that the shaft 41b is rotationally driven in the same direction and the reel 40b is rotated.

Further, the swing lever 56 is displaced in the direction of the arrow D2 to move the connecting member.
When 52 is angularly displaced about the axis of the support shaft 53, the second gear 47 meshes with the drive gear 29b and the rotation thereof is transmitted. The rotation of the second gear 47 is transmitted to the first gear 46, and thus the third gear 48 is rotationally driven in the same direction via the shaft 50. The rotation of the third gear 48 is transmitted to the reel gear 42a, so that the shaft 41a is rotationally driven and the reel 40a is rotationally driven.

By the rotation of the reel 40a or the reel 40b, the magnetic tape 33 of the magnetic tape cassette 32 is driven to run in the arrow C1 direction or the arrow C2 direction.

When the reel 40a is rotationally driven in this way, the shaft 28a coaxially fixed to the flywheel 25a and the pinch roller 30a are separated from each other, and the rotation of the drive gear 29a on the side that does not sandwich the magnetic tape 33 is magnetic. Since it is transmitted to the reel 40a that is performing the winding operation of the tape 33, when the variation in the rotation speed of the reel 40a is transmitted to the shaft 28a, the magnetic tape 33 is not affected by the variation. tape
The 33 can be driven to wind in the direction of arrow C1 and wound up.

5 is a plan view of another embodiment of the present invention, FIG. 6 is an exploded perspective view thereof, and FIG. 7 is an enlarged perspective view of a recording / reproducing idler gear train 60. The parts corresponding to those in the above-mentioned embodiment are designated by the same reference numerals. The magnetic tape recording / reproducing apparatus 20a of this embodiment is provided with a recording / reproducing idler gear train 60. Recording / playback idler gear train 60
Is fixed to the first gear 61 and coaxially with the first gear 61.
A second gear 62 having a smaller diameter than the gear 61, a third gear 63 meshing with the second gear 62, a fourth gear 64 fixed coaxially with the third gear 63 and having a smaller diameter than the third gear, and a fourth gear 64. And a fifth gear 65 meshing with. A shaft 66 is provided on the first gear 61 and the second gear 62.
Is inserted and is rotatably supported around its axis. A shaft 67 is inserted into the fifth gear 65 and is rotatably supported around its rotation axis. These shafts 66 and 67 are connecting members 6
A shaft hole 70, which is fixed to 8, and in which a support shaft 69 protruding from the chassis 21a is fitted at a central position between the shafts 66 and 67 of the connecting member 68.
Is formed. A pin hole 80 is formed at the end of the connecting member 68 on the shaft 67 side, and the pin 72 of the swing lever 71 is inserted into the pin hole 80 and connected.

When the swing lever 72 is driven to be displaced in the direction of arrow D2, the first gear 61 is connected to the drive gear 29a via the reduction gear 29a1 and the rotation thereof is transmitted, and the rotation of the first gear 61 is accompanied. The second gear 62 is driven, and the third gear 63 meshing with the second gear 62, and thus the fourth gear 64, drives the fifth gear 65 to rotate. The fifth gear 65 meshes with the reel gear 42b to transmit its rotation, and the rotation of the reel gear 42b is transmitted to the reel 40b via the shaft 41b. In this way, the rotation of the drive gear 29 can be decelerated and transmitted to the fifth gear 65. When the swing lever 72 is driven to be displaced in the direction of the arrow D1, the first gear 61 is connected to the drive gear 29b via the reduction gear 29b1 and its rotation is transmitted, and the second gear 62, the third gear The fifth gear 65 is rotationally driven via 63 and the fourth gear 64,
The rotation of 65 is transmitted to the reel gear 42a. Therefore, the rotation of the reel gear 42a is transmitted to the reel 40a via the shaft 41a.

By using such a recording / reproducing idler gear train 60, the rotation of the drive gear 29a or the drive gear 29b can be decelerated and transmitted to the reel gear 42b or the reel gear 42a.

According to the present invention, the rotation of the left drive gear is transmitted to the gear for the right reel and the rotation of the right drive gear is transmitted to the gear for the left reel by the power transmission mechanism, so that the magnetic tape cassette is wound. Even if the rotation speed of the left reel gear or the right reel gear on the take-up side varies when it is taken up, the variation of the take-up reel gear on the right drive gear or the left drive gear that is not on the take-up side The included rotational force is not transmitted. As a result, the magnetic tape of the magnetic tape cassette can be driven to travel by the driving force of the drive gear on the side that does not include variations in the rotation speed, and can be sent out at a constant speed. Therefore, at the time of recording / reproducing of the magnetic tape cassette, it is possible to record / reproduce with good sound quality without deteriorating the wow flatter performance described in connection with the prior art.

Further, since the power transmission mechanism is composed of a plurality of gears having different gear ratios, it is possible to reduce the rotational speed of the drive gear and transmit it to the reel gear. Need not be provided in relation to the drive gear, and thus the drive gear may have a single stage, which allows for a thinner device. Moreover, it is not necessary to provide an escape hole for the gear in the chassis, and only an escape hole for moving the shaft is required, which does not reduce the strength of the chassis.

[Brief description of drawings]

1 is a plan view of an embodiment of the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is an exploded perspective view thereof, FIG. 4 is a perspective view of a recording / reproducing idler gear train 45, and FIG. 6 is a plan view of another embodiment of the present invention, FIG. 6 is an exploded perspective view thereof, FIG. 7 is an enlarged perspective view of a recording / reproducing idler gear train 60, and FIG. 8 is a schematic diagram of a typical prior art. It is a perspective view which shows a structure. 20,20a ... Magnetic tape recording / reproducing device, 21,21a ... Chassis, 22 ... Drive motor, 25a, 25b ... Flywheel, 26 ... Belt, 29a, 29b ... Drive gear, 30a, 30b ... …
Pinch roller, 33 ... Magnetic tape, 36a, 36b ... Idler gear for rapid feed, 37a, 37b ... Shaft, 38a, 38b ... Swing arm, 39a, 39b ... Shaft, 40a, 40b ... Reel, 42a , 42b ……
Reel gears, 45,60 …… Recorder / playback idler gear train, 46,61 …… First gear, 47,62 …… Second gear, 48,63…
… 3rd gear, 49, 64 …… 4th gear, 65 …… 5th gear, 52
...... Coupling member, 53 …… Spindle

Claims (2)

[Scope of utility model registration request] 1. A left reel having a left drive gear and a right drive gear, which are rotationally driven in opposite directions to each other, and rotationally driven in the same directions as the respective rotational directions of the left and right drive gears, and a reel shaft protruding from the left reel. A gear and a right reel gear, and a power transmission mechanism interposed between the left and right drive gears and the left and right reel gears, a first gear and a second gear that have the same diameter and always mesh with each other, The first gear and the second gear are coaxially fixed to the common side, respectively, and have a third gear and a fourth gear each having a smaller diameter than the first gear and the second gear, and the first gear and the second gear. Is configured to be angularly displaceable around a position that is equidistant from each rotation center, and when either one of the first gear and the second gear meshes with the corresponding left drive gear or right drive gear, Either the first gear or the second gear on the other The power is transmitted to the corresponding left or right reel gear by the fixed third gear or the fourth gear, and the equidistant distance is used when switching the power transmitted to the left reel gear or the right reel gear. And such a power transmission mechanism that is driven to perform the angular displacement around a certain position. 2. A left reel having a left drive gear and a right drive gear which are rotationally driven in mutually opposite directions, and rotationally driven in the same direction as the respective rotational directions of the left and right drive gears, and a reel shaft protruding from the left reel. A power transmission mechanism interposed between a gear, a right reel gear, and left and right drive gears and left and right reel gears, which are rotationally driven by meshing with either the left drive gear or the right drive gear. A first gear, a second gear having a smaller diameter than the first gear, a third gear rotationally driven by the second gear, and a third gear coaxially formed with the first gear. , A fourth gear having a smaller diameter than the third gear, and a fifth gear that is rotationally driven by the fourth gear, wherein the rotation axes of the first gear, the second gear, and the fifth gear are the first gear. At the same distance from the rotation axes of the third gear and the fourth gear, And the fourth gear are configured to be angularly displaceable about the rotation axis of the fourth gear, and when the first gear is meshed with either the left or right drive gear, the fifth gear is either the left or right. Power is transmitted by meshing with the other reel gear, and when the left reel gear and the right reel gear are switched, the angular displacement is driven around the rotation axes of the third gear and the fourth gear. A reel shaft drive mechanism including such a power transmission mechanism.