JPS6083245A - Reel turntable driving mechanism of tape recorder - Google Patents

Abstract

PURPOSE:To facilitate a rotating speed changing and a normal/reverse changing mechanism by coupling three gears with a reel turntable coaxially, applying a turning force to a free gear among three, and engaging this gear to a large-diameter or small-diameter gear through a coupling gear. CONSTITUTION:A gear 10b engages the reel turntable 10e loosely and rotates in a free state, and the small-diameter gear 10a is pressed in the reel turntable 10e fixedly. The large-diameter gear 10c is pressed against the reel turntable 10e through the clutch mechanism consisting of a rotation stopper plate 10g and a polywasher 10h. Therefore, when a low-speed coupling gear 22a engages the gears 10b and 10c, gears 10b, 22-1a, 22-2a, and 10c engage with one another in order to rotate the reel turntable 10e at a reduced speed, and when a high-speed coupling gear 23a engages the gear 10b, gears 10b, 23-1a, 23-2a, and 10a engage with one another to rotate the reel turntable 103 at an increased speed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a drive mechanism for running and winding a tape in accordance with the operation mode of a tape recorder, and particularly relates to a drive mechanism for a reel stand. be.

[Background technology and its problems]

In a cassette tape recorder or the like, the tape winding direction and winding speed differ depending on the operation mode of the tape recorder, so the rotational force transmission mechanism becomes more complex as the operation modes become more diverse.

Conventionally, the rotation of the reel stand and the switching of the rotation direction are performed by changing the combination of many gears, so the arrangement of the control lever and the arrangement of the transmission mechanism that accompany the switching transmission mechanism occupy a large area. This makes it difficult to downsize and increases costs. In particular, when switching the operation mode using feather touch, a small control motor and plunger are used, and their arrangement poses a problem.

[Purpose of the invention]

This invention was made in view of the actual situation,
The present invention provides a reel stand drive mechanism for a tape recorder in which the transmission mechanism is simplified and downsized by using two-stage and three-stage float mechanisms.

[Summary of the invention]

In order to achieve the above object, the present invention includes a first gear having a large diameter coaxially connected to the reel stand via a slip mechanism;
a small-diameter second gear that is integrated with the reel stand;
An intermediate gear loosely fitted to the shaft of the reel stand is connected to the large-diameter first
gear or a small-diameter second gear. Therefore, the rotation speed of the reel stand can be easily changed, and the gears can be packed closely together in a small area, so that the transmission mechanism of the tape recorder can be made compact.

〔Example〕

FIG. 1 shows a plan view of the switching transmission mechanism showing the configuration of the main parts of the present invention, in which 1 is the rotating shaft of the drive motor M, 3
is the first shaft connected to the rotating shaft 1 by the belt 2.
This first reduction gear 3 is further coupled to a first rotating body 5 (gear) via a second reduction gear 4. A reversing lever 7 that pivotally supports the second rotating body 6 is loosely fitted onto the shaft of the first rotating body 5, and the reversing lever 7 is operated by the first rotating body 5. The second rotating bodies 5 and 6 are supported in a mutually meshed state. Then, the inverter 7 swings in the direction shown by the arrow A-H depending on the rotational direction of the first rotating body 5.

Reference numeral 8.9 indicates a pair of reel shafts, and each reel shaft 8.9 is equipped with a three-stage gear 10a as shown in the drive mechanism of the present invention.
, 70b, and IQc are arranged coaxially. Also, 1
Reference numeral 1 indicates a toothless gear that can mesh with the internal gear 6a of the second rotating body 6, and a toothless portion 11 is provided on a part of its outer periphery.
a is formed, and a pin I'lb is planted at an eccentric point on the inner periphery. A cam member 12 is arranged to abut against the pin 11b, and the cam member 12 is shifted left and right as shown by arrows C- and D when the partially toothed gear 11 rotates approximately half a turn.

13a and 13b are capstan shafts 14a and 14, respectively.
13a and 13b are shown.
are projecting pieces 12a, 1 formed at one end of the cam member 12.
It is controlled to move forward and backward by the rotation of shaft plates 15a and 15b that contact 2b.

16a and 16b are the pinch rollers 13a.

13b is shown urging the capstan shafts 14a and 14b to press against each other.

Although not shown, the cam member 12 may be moved to reverse the magnetic head during playback according to the running direction of the tape, or to control an azimuth adjustment mechanism.

Next, the portion indicated by the dashed line will be explained. 2
0 is a head board that is moved by a camshaft (not shown) of a motor for loading a cassette, and 21a and 21b are speed conversion levers that rotate when the head board 20 moves forward or backward in the direction of arrow E-F. Low-speed connecting gears 22 a , 22 b and high-speed connecting gears 23 a , 23 b , which are composed of two-stage gears, are respectively supported by the speed conversion levers 21 a and 21 b , and are supported by springs 24 a and 24 b . They are biased clockwise and counterclockwise, respectively.

And these connecting gears 22a, 22b.

23a and 23b are the three-stage gears 10a as described later.
, 10b, 10c to transmit rotational force to the reel shafts 8, 9.

Further, 25a and 25b indicated by two-dot chain lines are flywheels that are driven by the above-mentioned rotating shaft 1 through a belt 26 and rotate the capstan shafts 14a and 14b.

FIG. 2 shows a cross section of the drive mechanism taken along line aa' in FIG. 1, and the same reference numerals as in FIG. 1 indicate the same parts.

Next, the operation of the mechanism shown in FIG. 1 will be explained.

In the normal playback mode in which the tape drive motor M rotates in the direction of the solid line arrow, the belt 2° is rotated at the first . The first rotating body 5 is also rotated in the direction of the solid line arrow by the second reduction gears 3 and 4. Then, the reversal occurs and the par 7 is driven to rotate in the direction of arrow B, so the external gear 6b of the fourth rotary body 6 is brought to the reel shaft 9 side and meshes with the gear 10b as described later, resulting in low speed rotation. The reel shaft 9 is rotated in the direction of the solid arrow through the connecting gear 22b and the gear 10c, and the tape is wound onto the reel stand at the playback speed.

Also, at this time, the internal gear 6a of the second rotating body 6 comes into contact with the teeth of the partially toothed gear 11, so that the partially toothed portion 11a contacts the second rotating body 6, as shown in FIG. Rotate until it touches and stop. Therefore, the cam member 12 is moved in the direction of arrow C by the pin 11b, and the cam 81 (the shaft plate 15 on which the projecting piece 12a of the material 72 pivotally supports the pinch roller 13a)
deviate a. Therefore, the pinch roller 13a and the capstan shaft 14a are separated from each other, and the tape is wound onto the reel shaft 9 while being fed at a constant speed by the other pinch roller 13b and the capstan shaft 14b which are in contact with each other.

Next, we will explain the case where the auto-reverse mechanism operates from this state and shifts to reverse playback. In this case, the drive motor M starts reverse rotation as shown in Figure 3 by operating the switch or operating the reverse playback button. . Then, the belt 2° 1st. The second reduction gears 3, 4 and the first rotating body 5 are reversely rotated as shown by the dotted line, and the reversing lever 7 is moved in the direction of the six arrows. Therefore, the transmission system between the reel shaft 9 and the rotating body 6 of S2 is released, and the second rotating body 6 meshes with the gear 10b that drives the other reel shaft 8. Here, as described above, the gear 10c rotates via the low-speed connection gear 22a that is in contact with the gear 10b, and the reel shaft 8 rotates clockwise, thereby winding the tape at a constant speed.

At this time, when the reversing lever 7 moves in the direction A, the internal gear 6a of the second rotating body 6 comes into contact with the partially toothed gear 11, and rotates the partially toothed gear 11 in the direction of the dotted arrow. By this rotation, the pin 11b shifts the cam member 12 in the direction of the arrow, and presses the shaft plate 15b of the pinch roller 13b with its projection 12b.

And as shown, the pinch roller 13b,! 14. While leaving b in a detached state,
The pinch roller 13a and the capstan shaft 14a, which have been separated from each other, are pulled by the spring 16a and return to a pressed state.

Therefore, the tape being unwound from the reel shaft 9 is run in the opposite direction by the pinch roller 13a and the capstan shaft +4b, and is wound around the reel shaft 8, resulting in a reverse reproduction mode.

In this case as well, if necessary, the magnetic head is reversed and the azimuth is adjusted in conjunction with the movement of the cam member 12.

The forward and reverse operations have been explained above in the playback mode in which the head board 20 is moving forward, as shown by the dashed line. (plunger), the head substrate 20 is brought into a retracted state. Therefore, the magnetic head and pinch roller 13
a.

13b both retreat to positions away from the tape.

FIG. 4 shows the main part in such a state, in which the engaging piece 20a is formed on the head substrate 20 as the head substrate 20 retreats downward.

The tapered surface of 20b pushes out the pins of speed conversion levers 21a, 21b, and rotates speed conversion levers 21a, 21b against springs 24a, 24b. Therefore, in the forward or reverse playback mode, the reel shaft 8. The low-speed connecting gears 22a, 22b meshing with the gears 10b and 9 are separated, and the high-speed connecting gears 23a, 2
3 b will mesh with this.

Below, these two connecting gears 22a (22b).

The manner in which the rotational force of the second rotary body 6 is transmitted to the reel shaft 8 (9) by 23a (23b) will be explained.

FIG. 5 shows gears 10a and 10b of the reel shaft 8.

10a is a partial cross-sectional view in which 100 is shown with diagonal lines.

10b and 10C are the aforementioned three-stage gears, 10d is a reel pawl, 10e is a reel stand, 10f is a spring, 10g is a rotation stop plate, and 10hl is a polywasher.

The aforementioned gear 10b is loosely fitted to the reel stand 10e and rotates freely, and the small diameter gear 10a is loosely fitted to the reel stand 10e.
It is press-fitted and fixed. In addition, the large diameter gear 10c includes a spring 10f, a rotation stop plate 10g, a poly 7 spring 10
It is press-fitted to the reel stand 10e via a clutch mechanism consisting of h.

Furthermore, the low-speed connecting gear 22a is made up of two-stage gears 22-1a and 22-2a, and the high-speed connecting gear 23a is made up of two gears 22-1a and 22-2a having different diameters.
3-'1a and 23-2a are integrated.

Therefore, the low speed connection gear 22a is connected to the gears 10b and 1.
When meshing with 0c, gear 10b → gear 22-1a → gear 2
2-2a→Connects with gear 10c, speeds up and rotates reel stand 10e, and high-speed connection gear 23a connects to gear 10b
When engaged, gear 10b-+gear 23-1a+gear 2
3-2a+gear 10a, and rotates the reel stand 10e at increased speed. In addition, gear 23-2a
may be coupled via a spring plate P to provide a slip mechanism, and the lower surface of the gear 10a may be used as a black and white reflector for detecting the number of rotations.

As a gear mechanism for speed conversion, connecting gears 22a (22b) and 23a (23b) for low speed and high speed are used. The mechanism allows speed conversion to occur with a single connecting gear.

〔Effect of the invention〕

As explained above, the reel stand driving mechanism of the tape recorder of the present invention connects three gears coaxially to the reel stand, and applies rotational force to the free gear among them.
Since this gear is connected to a large-diameter gear or a small-diameter gear by a connecting gear, the mechanism for changing the rotation speed and normal reverse is simplified, making it possible to achieve smaller size and lower cost. There are advantages.

[Brief explanation of drawings]

Fig. 1 is a plan view of the transmission mechanism in the tape recorder of the present invention, Fig. 2 is a sectional view taken along line a-a' in Fig. 1, and Fig. 3 is the operation of Fig. 1 when switching to reverse playback. figure,
FIG. 4 is a plan view of the transmission mechanism in a tape fast-forwarding state;
FIG. 5 shows a layout of gears for driving the reel stand. In the figure, 10a is a small diameter gear, 10b is an intermediate gear, 10
c is a large diameter gear, 10d is a reel pawl, 10e is a reel stand, 22a (22b) is a low speed connection gear, 23a (23
b) shows a high-speed connection gear.

Claims (1)

[Claims] A first gear with a large diameter is coaxially connected via a slip mechanism to a reel stand that rotates integrally with the reel pawl, a second gear with a small diameter that rotates integrally with the reel stand, and a second gear with a small diameter that rotates integrally with the reel stand; An intermediate gear loosely fitted to the reel stand is attached, and the rotational force transmitted to the intermediate gear is transferred to the first gear. Alternatively, a reel stand drive mechanism for a tape recorder, characterized in that the reel stand is configured to rotate at high speed and at low speed by controlling a connecting gear that can be coupled to a second gear.