JPH0514978B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a method for reliably starting and stopping the rotation of a reel shaft at desired timing in relation to the movement of a magnetic head toward and away from a magnetic tape. Regarding the tape recorder.

[Conventional technology]

In a tape recorder, the head mounting member is moved forward and the magnetic head attached to it is brought into contact with the magnetic tape to enter the recording or playback state, and when the head mounting member is stopped, the head mounting member is moved backward to remove the magnetic head from the magnetic tape. It is common practice to separate them.

Further, the switch of the motor for driving the reel shaft is set to be turned off when the head mounting member is in the retracted position, and switched from off to on in connection with the forward movement of the head mounting member.

In this case, in order to ensure that the motor reaches a predetermined number of revolutions by the time the magnetic head contacts the magnetic tape, it is desirable to start the motor as soon as possible, so the head mounting member is moved to the retracted position. The switch is set to turn from off to on when the vehicle moves forward slightly.

Furthermore, if the reel shaft begins to rotate before the magnetic head comes into contact with the magnetic tape, the magnetic tape will be fed before the magnetic head comes into contact with it, causing the recording or playback position to move. For this reason, a clutch mechanism is provided in the rotation transmission mechanism that transmits the rotational force from the motor to the reel shaft, and when the head mounting member is in the retracted position, this clutch mechanism is set to ``disengaged''. Immediately before the magnetic head comes into contact with the magnetic tape as it moves forward, the clutch mechanism is switched to the "joint" position, so that the time when the rotation of the reel shaft starts almost coincides with the time when the magnetic head comes into contact with the magnetic tape.

A simple example of such a clutch mechanism is shown in FIG.

This is configured to transmit the rotational force of a motor 101 to a reel shaft 109 via a motor pulley 102, an endless belt 103, a pulley 104, gears 105 to 107, and a reel shaft gear 108.
07 is supported by a movable member 110 that can rotate around a reel shaft 109, and this movable member 11
0 in one direction by a spring 111 to cause the gear 107 to mesh with the gear 106. In addition, for the sake of simplicity in the drawings, all the gears are shown as simple circles (pitch circles), and the meshing parts of the gears are shown as black dots (the same applies to other drawings). Here, the two gears 106 and 107 constitute a clutch mechanism. That is, when the movable member 110 is rotated in the other direction against the spring 111, the gears 106 and 107 are separated and the rotation transmission path from the motor 101 to the reel shaft 109 is cut off. Therefore, in order to associate the forward and backward movements of the head mounting member with the "connection" and "disconnection" actions of the clutch mechanism, it is necessary to
The rotating end of 10 may be pulled back against the spring 111.

[Problem that the invention seeks to solve]

By the way, as shown in Fig. 10, two gears 10
When configuring a clutch mechanism that operates in conjunction with the movement of the head mounting member by making the clutches 6 and 107 engageable and detachable, the following points should be kept in mind.

(1) Both gears 106 and 107 should be quickly engaged and disengaged.

(2) When meshing both gears 106 and 107, take measures to prevent the gear teeth from interfering with each other.

Therefore, first considering point (1) using FIG. 11, one gear 107 is replaced by the other gear 106
In order to quickly engage and disengage the gear 106
It is desirable that the moving direction of the gears 106 and 107 coincide with the direction of a straight line connecting the centers of the gears 106 and 107 (arrows A and A').

However, regarding point (2) above, gear 1
It is clear that when the moving direction of gear 07 is made to match the straight line l, interference between the teeth of both gears 106 and 107 as shown in the figure is most likely to occur. Therefore, it is desirable to set the moving direction of the gear 107 in a direction that intersects the straight line 1 (arrows B and B').

The present invention has been made based on the above considerations, and an object of the present invention is to configure at least a part of a rotation transmission mechanism that transmits the rotational force of a motor to a reel shaft with a pair of gears that mesh with each other, and to The rotation transmission path is connected and disconnected by engaging and disengaging both gears in connection with the movement of the head, and when the head mounting member moves forward, the motor is switched off as soon as possible in consideration of the start-up of the motor. In a tape recorder in which the start of rotation of the reel shaft is almost the same as the time when the magnetic head contacts the magnetic tape, when the two gears mesh, the gears do not interfere with each other.
Moreover, the purpose is to quickly engage and disengage both gears.

[Means for solving problems]

In order to achieve the above objects, the tape recorder of the present invention includes a reel shaft into which a reel of magnetic tape is loaded, a motor for driving the reel shaft, and a pair of gears that mesh with each other at least. a rotation transmission mechanism that transmits rotational force from the rotation transmission mechanism to the reel shaft; and first and second rotation transmission mechanisms that respectively support the pair of gears of the rotation transmission mechanism and are movably provided so as to be able to engage and detach the pair of gears. a movable member, a head mounting member that carries a magnetic head and is provided to move forward and backward, and moves the magnetic head toward and away from the magnetic tape as the head moves forward and backward; and a head mounting member that responds to the forward movement of the head mounting member. a switch that starts the motor in response to a backward movement of the head mounting member and stops the motor in response to a backward movement of the head mounting member; When the head mounting member advances to a predetermined position, the first and second movable members are moved to engage the pair of gears, and when the head mounting member begins to move backward, the pair of gears are moved apart. the first and second movable members to move the first and second movable members, respectively, so that when the pair of gears are engaged and disengaged, the pair of gears are moved to a center position in the meshed state. The moving direction of the first and second movable members is set such that the pair of gears are moved in a direction intersecting a straight line connecting them, and in a direction that causes the pair of gears to bite into each other when engaged. It is a feature.

[Effect]

In the above configuration, the pair of gears constituting the clutch mechanism move in the direction of engagement and disengagement with each other as the head mounting member advances and retreats. In this case, since the direction of engagement and disengagement of both gears is different from the direction of the straight line connecting the centers when both gears are in mesh, there is no interference between the tooth teeth when both gears mesh. Reliable and smooth engagement is achieved. Further, even when the two gears are separated, since both gears are moved, the separation is performed smoothly. Therefore, it is possible to reliably start and stop the rotation of the reel shaft at desired timings in relation to the forward and backward movement of the head mounting member.

〔Example〕

An embodiment of the present invention is shown in FIGS. 1 to 9. Figure 1 shows the schematic configuration of a cassette tape recorder, in which 1 is the tape recorder board;
Reference numerals 2a and 2b indicate reel shafts on the tape supply side and tape winding side, respectively, and reels in a tape cassette (not shown) are loaded onto both reel shafts 2a and 2b. A capstan shaft 3, a pinch roller support member, and a head mounting member 5 are attached to the upper surface side of the tape recorder board 1. The head mounting member 5 is provided so as to be able to move forward and backward in the vertical direction in the figure, and is always urged in the return direction (downward in the figure) by a return spring 5a. The head mounting member 5 is provided with first and second engaging portions 6 and 7, both of which are integrally provided with the head mounting member 5. The pinch roller support 4 is
One end thereof is rotatably supported on the substrate 1 via a shaft 4a, and the rotating end rotatably supports the pinch roller 8. A recording/playback magnetic head 9 is mounted on the head mounting member 5, and by moving the head mounting member 5 forward and backward,
The magnetic head 9 is configured to move toward and away from the magnetic tape in the tape cassette. Further, a bar spring 10 is attached to a part of the head mounting member 5, and one end of this bar spring 10 is engaged with the rotating end portion of the pinch roller support 4 to control the forward and backward movement of the head mounting member 5. Accordingly, the pinch roller 8 is moved toward and away from the capstan shaft 3.
An erasing head 11 is mounted on the head mounting member 5, and operating members 12-17 for recording, playback, rewind, fast forward, stop, and pause are mounted on the bottom side of the board 1 from left to right. In addition, 12 in the figure
a is a return spring 1 that urges both the recording and playback operating members 12 and 13 in the return direction (downward in the figure);
Reference numeral 4a indicates a return spring that biases both the rewind and fast forward operation members 14 and 15 in the return direction, and 16a indicates a return spring that biases both the stop and pause operation members 16 and 17 in the return direction. The head attachment member 5 is a regeneration operation member 1 by regeneration operation.
3 moves forward, and is locked in the advanced position by a locking mechanism (not shown), and is released from the locked state by moving the stop operation member 16 forward due to the stop operation, and returns to the backward position by the return spring 5a. It is something to do.

FIG. 2 shows a rotation transmission mechanism that transmits rotational force from a drive source to the reel shafts 2a, 2b and the capstan shaft 3.
The rotational force is transmitted to the capstan pulley 20 via the endless belt 19, and further transmitted from another capstan pulley 21 to the switching pulley 23 via the endless belt 22. The switching pulley 23 is the shaft 2
4 as a fulcrum, and the first movable member 25 further includes a switching pulley 2 coaxially with the switching pulley 23.
A pair of large and small switching gears 26 and 27 that rotate together are supported between the switching gears 3 and 3 via a friction transmission mechanism (not shown). On the other hand, the reel shaft 2a on the tape supply side
A reel shaft gear 28 is attached to the base end of the reel shaft 2b, and a pair of reel shaft gears 29 and 30 are attached to the base end of the reel shaft 2b on the tape winding side.
and a friction transmission mechanism (not shown). Further, a second movable member 31 is provided which is rotatable around the reel shaft 2b on the tape winding side, and this movable member 31 has an idler gear 32.
is supported so as to always mesh with the reel shaft gear 29 on the tape winding side. And the first and second
The movable members 25 and 31 are arranged in a substantially orthogonal relationship in the plan view, and the rotation of these movable members 25 and 31 allows the small switching gear 2 supported by each to be
7 and the idler gear 32 are configured to engage and disengage from each other, and these gears 27 and 32 constitute a set of clutch mechanisms. As shown in FIG. 3, when both gears 27 and 32 engage and disengage each other, the engagement and disengagement directions of the contact points P of the pitch circles of both gears are as shown in the figure as representative directions A and A'. Both gears are set to intersect with a straight line l connecting the centers of both gears in a meshed state. Furthermore, a fast-forwarding gear 33 that constantly meshes with the reel shaft gear 30 is arranged near the reel shaft 2b on the tape winding side.

The first movable member 25 is biased clockwise in the drawing by a spring 25a, and has a first engaged portion 34 corresponding to the first engaging portion 6 of the head mounting member 5 at its rotation end. It is installed protrudingly. The rotation of the first movable member 25 by the spring 25a is inhibited by the contact of the portion 15b of the fast-forward operation member 15 with the first engaged portion 34. Further, the second movable member 31 is urged clockwise in the drawing by a spring 31a,
A second engaged portion 36 corresponding to the second engaging portion 7 of the head mounting member 5 is bent at the pivoting end. The rotation of the second movable member 31 by the spring 31a is caused by the rotation of the second movable member 31.
This is prohibited by the second engaging portion 7 of the head mounting member 5 coming into contact with the head mounting member 6.

The tape recorder board 1 is provided with a switch 37 for controlling rotation and stopping of the motor 18, as shown in FIG. Reference numeral 38 in the figure is a slide plate that moves in the left and right directions in the figure in conjunction with the forward and backward movement of the playback operation member 13, and when the playback operation member 13, the rewind operation member 14 or the fast-forward operation member 15 moves forward, The slide plate 38 has an inclined surface 3 provided corresponding to those operating members.
8a, 38b, or 38c is pushed by a part of the playback, rewind, or fast-forward operation member and moves to the right in the figure, thereby switching the switch 37 from off to on.

Now, when the head mounting member 5 is in the retracted position as shown in FIG. 1, the second movable member 31 is moved by the engagement between the second engaging portion 7 and the second engaged portion 36. The idler gear 32 is in a position rotated counterclockwise in the drawing against the spring 31a, and the idler gear 32 is spaced apart from the small switching gear 27. Further, the switch 37 is kept in an off state.

Here, due to the regeneration operation, the regeneration operation member 13
When the head mounting member 5 moves forward, the slide plate 38 moves to the right and switches the switch 37 from off to on.
Start the motor 18. As the head mounting member 5 moves forward, the first movable member 25 moves to the fifth movable member 25.
As shown in the figure, the engagement between the first engaging part 6 and the first engaged part 34 causes it to rotate counterclockwise, but the engaged part 34 touches the top end of the engaging part 6. After crossing it, it is then rotated clockwise by the spring 25a. On the other hand, when the head mounting member 5 moves forward, the second movable member 31 is rotated clockwise following the movement of the spring 31a. The rotation of the first and second movable members 25 and 31 causes the small switching gear 27 and the idler gear 32 to approach each other, and at the same time as the head mounting member 5 reaches a predetermined operating position, both gears 27 ,32
mesh with each other. At this time, both gears 27, 32
As shown in Figure 6, the line of motion intersects the straight line l that connects the centers when both gears are meshed, so there is a very low possibility that the teeth of both gears will interfere with each other, and both gears will operate smoothly. It will mesh with the When the head mounting member 5 reaches a predetermined operating position, the rotational force of the motor 18 is transferred to the pulleys 20 and 2 due to the meshing of both the gears 27 and 32.
1, 23 and gears 27, 32, 29 to the reel shaft 2b on the tape winding side (7th
figure). Note that as the head mounting member 5 moves forward, the pinch roller support 4 also rotates clockwise.
Since the pinch roller 8 presses against the capstan shaft 3 with the magnetic tape in between, the head mounting member 5
The reproducing operation is started immediately when the controller reaches the predetermined operating position.

Next, when the stop operating member 16 is advanced by a stop operation during the reproducing operation, the head mounting member 5 is released from the locked state at the operating position and returned by the spring 5a. Here, when the head mounting member 5 starts to retreat, the first movable member 25 is moved by the engagement between the first engaging portion 6 and the first engaged portion 34.
rotates counterclockwise, and the second movable member 31 rotates counterclockwise due to the engagement between the second engaging portion 7 and the second engaged portion 36. For this reason,
The gears 27 and 32 supported by the respective movable members 25 and 31 move simultaneously in the direction away from each other, and both gears quickly release their meshing state. Then, when the head mounting member 5 further retreats and reaches near the stop position, the slide plate 38 moves to the left to switch the switch 37 from on to off.
This causes the motor 18 to stop.

Note that when the fast-forward operation member 15 is advanced by a fast-forward operation in the stopped state shown in FIG. The movable member 25 is rotated clockwise by a spring 25a to mesh the large switching gear 26 with the fast-forwarding gear 33. Therefore, the rotational force of the motor 18 is applied to the pulleys 20, 21, 23 and the gears 26, 33, 30.
is transmitted to the reel shaft 2b on the tape winding side, and the reel shaft 2b rotates at high speed in the tape winding direction (FIG. 8).

In addition, the rewinding operation member 1
4, the part 14b of the rewind operation member 14 comes to push the engaged portion 34 of the first movable member 25, and the first movable member 25 rotates counterclockwise. The large switching gear 26 is brought into mesh with the reel shaft gear 28 on the tape supply side. Therefore, motor 1
The rotational force of 8 is transmitted to the reel shaft 2a on the tape supply side via pulleys 20, 21, 23 and gears 26, 28.
This causes the reel shaft 2a to rotate at high speed in the tape rewinding direction (FIG. 9).

〔Effect of the invention〕

As described above in detail based on the embodiments, according to the tape recorder of the present invention, the clutch mechanism for starting and stopping the rotation of the reel shaft in relation to the forward and backward movement of the head mounting member is constituted by a pair of gears, The pair of gears are engaged and disengaged in relation to the advance and retreat of the head mounting member, and when the gears are engaged and disengaged, the direction of engagement and disengagement of the contact points of the pitch circles of both gears is a straight line connecting the centers of both gears in the meshed state. Since both gears are moved to intersect with each other, it is possible to prevent the teeth from interfering with each other when the two gears are engaged, ensuring reliable and smooth engagement. Since both gears are moved during separation, smooth separation can be achieved. In other words, when one of a pair of gears is engaged and disengaged from the other, if the moving direction of the one gear is set to intersect the straight line connecting the centers of both gears, then when both gears mesh, Although this has the advantage that the gears are less likely to interfere with each other, it also means that the two gears cannot be separated quickly.However, in the present invention, since both gears that mesh with each other are moved, the separation of the two gears is also possible. This will be done quickly. Therefore, it is possible to reliably start and stop the rotation of the reel shaft at desired timings in relation to the forward and backward movement of the head mounting member.

[Brief explanation of the drawing]

1 to 9 show one embodiment of the present invention, in which FIG. 1 is a plan view of a cassette tape recorder, FIG. 2 is a plan view showing the rotation transmission mechanism, and FIG.
FIG. 4 is a plan view showing the relationship between a pair of gears that can be engaged and disengaged from each other, FIG. 4 is a plan view showing the relationship between the operating member and the switch, and FIG. 5 is a plan view showing the relationship between the first movable member and the head mounting member. FIG. 6 is a plan view showing the relationship between a pair of gears that can be engaged and disengaged from each other, FIGS. 7 to 9 are plan views of the rotation transmission mechanism in different operating states, and FIG. 10 is a plan view of a conventional example. The plan views shown in FIGS. 11 and 12 are plan views for explaining the problems. 2a, 2b... Reel shaft, 5... Head attachment member, 6... First engaging part, 7... Second engaging part, 9... Magnetic head for recording/playback, 13... Playback operation Member, 16...Stop operation member, 18...Motor, 25...First movable member, 27...Switching gear, 31...Second movable member, 32...Idler gear, 37...Switch, P... ...Gear, 27,3
Point of contact between pitch circles of No. 2, l... A straight line connecting the centers of gears 27 and 32.

Claims (1)

[Claims] 1. A reel shaft on which a reel of magnetic tape is loaded, a motor for driving the reel shaft, and a rotation transmission mechanism that transmits rotational force from the motor to the reel shaft, including at least a pair of mutually meshing gears; First and second movable members each support the pair of gears of the rotation transmission mechanism and are movably provided so as to be able to engage and detach the pair of gears, and a magnetic head is mounted on the first and second movable members and the movable member is provided so as to be movable forward and backward. a head mounting member that moves the magnetic head toward and away from the magnetic tape as the head moves forward and backward; and a head mounting member that starts the motor in response to the forward movement of the head mounting member and moves the head mounting member backward. a switch that stops the motor in response to the operation; and a switch that is provided on the head mounting member so as to be engageable with the first and second movable members, and that when the head mounting member advances to a predetermined position, moving the first and second movable members to engage the gears, and moving the first and second movable members to separate the pair of gears when the head mounting member begins to retreat; and a first and second engaging portion, when the pair of gears are engaged and disengaged, the pair of gears are arranged in a direction intersecting a straight line connecting the centers in the meshed state, and when the gears are engaged, A tape recorder characterized in that the moving directions of the first and second movable members are set so that the pair of gears are moved in a direction that bites into each other.