JPH0630189B2 - Magnetic recording / reproducing device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a magnetic recording / reproducing apparatus such as a video tape recorder.

2. Description of the Related Art In recent years, a magnetic recording / reproducing apparatus such as a video tape recorder is desired to be small, lightweight, thin, and have high performance and low cost.

Hereinafter, an example of the reel driving mechanism of the above-described conventional magnetic recording / reproducing apparatus will be described with reference to the drawings.

6 (a) and 6 (b) are plan views of a reel drive mechanism of a conventional magnetic recording / reproducing apparatus, FIG. 7 is a sectional view showing a meshing relationship, and FIGS. 8 to 10 are diagrams for explaining the operation thereof. It is a top view.
In FIGS. 6 and 7, 1 is a reel stand on which a tape (not shown) is mounted and driven, 22 is a drive gear for driving the reel stand 1, 24 is coaxial with the drive gear 22 and via a clutch mechanism. Clutch gear for transmitting rotation and torque to the drive gear 22, 23 is a clutch spring for generating a clutch force, and 25 is a clutch gear 2
4 is a clutch felt that generates a frictional force between the clutch gear 24 and the drive gear 22 and transmits the rotation of the clutch gear 24 to the drive gear 22 with a set torque, and 26 is a stopper ring that integrates the clutch mechanism.

These 22, 23, 24, 25 and 26 form a clutch mechanism. When the clutch gear 24 is driven, a constant torque is transmitted to the reel base 1 via the clutch mechanism. Further, since the rotation speed of the reel base 1 during driving is via the clutch mechanism, it can take any value as long as it is lower than the rotation generated by the clutch gear 24.

Reference numeral 29 is a relay gear that transmits rotation from a drive source such as a capstan, and 31 is a plan view of the upper layer. As shown in FIG. 6 (b), rotation and torque from the drive source are directly transmitted via the drive gear 24. On the idler gear transmitted to the reel stand 1, 32 is on the idler gear shaft which is the center of rotation of the idler gear 31,
Reference numeral 33 denotes the rotation and torque from the drive source shown in the plan view FIG. 6 (a) and the sectional view FIG. 7 of the lower layer and indirectly transmitted to the reel stand 1 via the drive gear 24 via the clutch mechanism. Under the idler gear, 34 is below the idler gear shaft which is the center of rotation of the idler gear 33, and 30 is the reel stand to be driven by selectively rotating the idler gear upper and idler gear lower left and right (arrow C in FIG. 6 (b)). No. 1 (the reel stand 1 on the left side and the drive gear are not shown) is an idler felt for generating a clutch force by frictional force, 36 is an idler spring for generating a clutch force in the idler, 28
Supports an idler gear shaft which is a rotation support shaft on the idler gear, and supports an idler gear shaft which is a rotation support shaft below the idler gear, and 37 supports an idler gear shaft which is a rotation support shaft below the idler gear. It is also under the idler arm that constitutes a support arm for left and right rotation under the idler mechanism. Also, 28, 30, 31, 32,
A mechanism composed of 36 is added to the idler mechanism, and further 3
A mechanism composed of 0, 33, 35 and 36 is called an under idler mechanism.

27 is a left and right rotation on the idler mechanism in various modes,
Reference numeral 35 is a control plate for restricting or releasing the restriction, and 35 is a control plate for performing the same operation as under the idler mechanism. Reference numeral 19 is a reel shaft which is a rotation center of the reel stand 1, 20 is a drive gear and a drive gear shaft which is a rotation center of the clutch gear 24, 21 is a relay gear shaft which is a rotation center of the relay gear 29, and 18 are 19 and 20. , 21 for fixing the respective axes. Further, h ₁ represents the height of the reel base drive mechanism.

The operation of the reel drive mechanism of the conventional magnetic recording / reproducing apparatus configured as described above will be described below.

First, the driving operation of the reel stand 1 will be described.

In the magnetic recording / reproducing apparatus, the operation of the idler mechanism is limited by the selection of each mode provided.

As a first transmission example, the transmission state shown in FIGS. 6 (a), (b) and FIG. 7 will be described. First, as shown in FIGS. 6 (a) and 7, the operation of the lower control plate 35 causes the lower operation of the idler mechanism to be fixed with its rotational movement restricted. In this state, the idler mechanism cannot engage with the clutch gear 24, so that the reel base 1 is not driven by the clutch mechanism. On the other hand, when the control plate 31 moves and the restriction of the rotation operation on the idler mechanism is released, the idler can be rotated in any direction, and the idler mechanism can be rotated as shown in FIG. 6 (b). , Can be engaged with the drive gear 22. Next, when the tape running state is reached and the rotation and torque from the capstan or reel motor (not shown) are transmitted to the relay gear 29, the rotation and torque are transmitted to the reel gear by the drive gear on the idler mechanism. It is transmitted directly to the table 1.

However, in this transmission system, since rotation and torque are directly transmitted, the tape (not shown) is fed at a constant speed.
In the recording and reproducing mode in which the reel base 1 is driven, when the capstan is used as the drive source of the reel base 1, the rotational speed of the capstan that is the drive source is constant, but the driven reel base 1 is the tape. However, there is a contradictory problem that the number of revolutions is constantly changing because it is wound up. Further, even when the reel base is driven by using another motor, the reel base 1 needs to be driven with a torque equal to or lower than a certain value in order to drive the tape in a stable state. There is a problem in that it cannot be used in combination with the mode requiring the torque. Therefore, in the conventional magnetic recording / reproducing apparatus, as shown in FIG.
Two upper and lower transmission systems are provided in order to separate the torque on the reel stand 1 from the rotational speed of the drive source and the torque. Transmission gear 29
Rotation and torque are transmitted to the upper and lower portions of the idler mechanism as in the first transmission system. However, when the second transmission system is selected, the operation on the idler mechanism is limited, and the idler mechanism does not mesh with the drive gear 24.

On the other hand, under the idler mechanism, the restriction by the lower control plate is released, and under the idler mechanism, the drive gear 24 is rotated through the meshing clutch mechanism with the clutch gear 24, and the reel base 1 is set with the set torque and the set rotation speed. Rotate. Here, since the drive gear 24 is rotated via the clutch mechanism, the reel base 1 and the rotation speed and the rotation speed of the clutch gear 24, which is directly transmitted from the drive source, have a constant relationship. There is no need here, there is a second transmission system.

Next, how the two transmission systems are actually selected and operated will be described.

FIG. 8 shows the states of the tape fast-forwarding and rewinding operations of the magnetic recording / reproducing apparatus. If the upper and lower idlers are piled up, the drawing becomes difficult to see. Therefore, FIG. 8 (b) shows the top of the idler mechanism as a plan view of the upper layer and FIG. 8 (a) shows the bottom of the idler mechanism as a plan view of the lower layer. Actually, as apparent from FIG. 7, the transmission gear 29 is in the coaxial position.

First, a mode selection mechanism (not shown) operates to drive the upper control plate 35 and the lower control plate 35. The control plate stops at the position shown in FIG. 8 and the restriction on the idler mechanism is released. At the same time, the bottom of the control plate moves to the position shown in FIG. 8 to limit the operation under the idler mechanism.
Here, the first transmission system is selected. When the relay gear 29 is driven by the drive source in this state, the torque and the rotational speed of the drive source are directly transmitted to the reel stand 1 according to the reduction ratio thereof, and the magnetic recording / reproducing apparatus fast-forwards or winds. Perform the return operation.

FIG. 9 shows the state of the braking mode. Note that (a) is a plan view of the lower layer, and (b) is a plan view of the upper layer. From the tape fast-forward mode or the like shown in FIG. 8, the upper control plate and the lower control plate move to the control side in order to separate the upper and lower idler mechanisms from the reel base 1. (Figure 9 arrow E direction)
Next, the reel base 1 and the drive gear 22 and the clutch gear 24, which are separated from the drive force from the drive source, try to rotate by inertial force, but the control mechanism (not shown) that operates together with the upper and lower sides of the control plate is the reel. The reel base 1, the drive gear 22, and the clutch gear 24 are brought into contact with the base 1 and exert a braking force.
Will stop.

FIG. 10 shows a recording and reproducing mode. Similarly, (a) is a plan view of the lower layer, and (b) is a plan view of the upper layer.

First, the mode selection mechanism (not shown) shifts to the recording / reproducing mode, and the lower control plate operates from the limit mode to the release mode (direction of arrow F).

On the other hand, since it remains in the restricted mode on the control plate,
It does not work on the idler mechanism. The second transmission system is selected here, and as described above, it becomes possible to run the tape at a constant speed and wind the tape with a constant torque.

Problems to be Solved by the Invention However, the above-mentioned configuration has a drawback that the structure is complicated and the number of parts is large because two sets of idler mechanisms are required. Furthermore, since the two sets of idler mechanisms are upper and lower two layers, the thickness h ₁ of the reel drive mechanism is relatively large,
This has been an obstacle to miniaturization and thinning of the magnetic recording / reproducing apparatus.

In view of the above-mentioned problems, the present invention provides a magnetic recording / reproducing apparatus which is simplified by using only one idler mechanism and which can be made thin.

Means for Solving the Problems In order to solve the above problems, a magnetic recording / reproducing apparatus of the present invention includes a reel base on which a tape is mounted, first and second drive gears for driving the reel base, and In a reel drive mechanism including an idler that drives the reel base via a first or second drive gear, at least one drive gear of the first and second drive gears is relative to a rotation shaft of the drive gear. It is movable in the vertical direction, and one of the first and second drive gears selectively meshes with the idler to drive the reel stand.

Operation The present invention has a single idler mechanism with the above-described configuration, which not only simplifies the configuration and reduces the number of parts, but also enables thinning of the device. Also, the first
And by selectively moving the second drive gear,
It is possible to have the same function as the conventional one.

Embodiment Hereinafter, a magnetic recording / reproducing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of relevant parts of a reel drive mechanism of a magnetic recording / reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view showing a meshed state, and FIGS. FIG. In FIG. 1, 1 is a tape (not shown)
A reel base 3 for mounting and driving a clutch gear 3 which is coaxial with the reel base 1 and which transmits rotation and torque to the reel base 1 via a clutch mechanism, 4 is a part of the clutch mechanism, and a clutch force. A clutch spring 2 for generating a frictional force between the clutch gear 3 and the clutch gear 3, and a clutch felt 5 for transmitting the rotation of the clutch gear 3 to the reel base 1 with a set torque are integrated with the reel base 1. The rotation speed and torque are directly transmitted to the reel base 1 by a stopper gear that is integrated with the clutch mechanism provided on the reel base. These 1, 2, 3, 4, 5 form a clutch mechanism in the reel base 1, and when the clutch gear 3 is driven, a constant torque is transmitted to the reel base 1. Also reel stand 1
The number of revolutions can be arbitrarily selected as long as it is lower than the number of revolutions of the clutch gear 3.

Reference numeral 7 is a first drive gear provided to drive the reel base indirectly via a clutch gear, 6 is a first drive gear shaft which is a rotation center of the first drive gear, and 8 is a fixed first drive shaft. Then
A drive plate that supports the first drive gear, 9 is a second drive gear that is provided to directly drive the reel base via a stopper gear, and 15 is a relay gear that transmits rotation from a drive source such as a capstan. Reference numeral 10 denotes an idler gear that meshes with a first drive gear 6 provided to indirectly transmit the rotation and torque from the drive source to the reel base 1, and 11 is coaxial with the idler gear, but the rotation and torque from the drive source are A lower idler gear that meshes with a second drive gear 9 provided to directly transmit to the reel stand 1, 12 is an idler shaft that is a rotation shaft of the idler gear upper portion 10 and the idler gear lower portion 11, and 13 is a rotation of the idler mechanism while supporting the idler shaft. The idler arm, which serves as an arm at the time, generates frictional force between the idler arm and the relay gear 15 in the idler mechanism, and the idler arm 14 is operated with the set torque. Idler felt rotating the Raamu 13, 16 Aidorabane for generating the clutch force, 17 is a sleeve that is provided so as to integrate the idler mechanism, rotatably supports the relay gear 15, to secure the idler arm. 18 is a board on which the mechanical parts of the device are mounted,
Numeral 19 rotatably supports the reel stand 1, a reel shaft provided on the substrate 18, rotatably supports the second drive gear 9 on the substrate 18, a drive shaft provided on the substrate 19, and 21 the sleeve 1.
7 is rotatably supported and is also provided on the substrate by an idler shaft which is also the movable center of the idler mechanism. Also h ₂
Indicates the height of the reel drive mechanism.

The operation of the reel drive mechanism of the magnetic recording / reproducing apparatus according to the present embodiment configured as described above will be described below.

First, the driving operation of the reel base 1 will be described with reference to FIGS. 1 and 2. First, the drive plate 8 is moved so as to reach the setting state of each mode provided in the magnetic recording / reproducing apparatus, and the state shown in FIG. 1 is obtained.
Selected to mesh with 1. In this state, the idler gear upper 10 and the first drive gear 7 never mesh with each other, and this state is the second transmission system. Next, the rotation and torque from the capstan or reel motor (not shown) are transmitted to the relay gear 15. The rotation and torque transmitted to the relay gear are directly transmitted to the idler gear lower portion 11, the second drive gear 9, the stopper gear 5, and the reel stand 1.

Next, the first transmission system will be described. First, the drive plate 8 moves, and unlike FIG. 1, moves to a position where the first drive gear 7 and the idler gear upper 10 are selectively meshed with each other (fifth embodiment).
See figure). This state is the first transmission system, and the second drive gear 9 and the lower idler gear 11 never mesh with each other.

Next, a capstan or reel motor (not shown)
The rotation and the torque from are transmitted to the relay gear 15. The rotation and torque transmitted to the relay gear are indirectly transmitted to the idler gear 10, the first drive gear 7, the clutch gear 3, the reel stand 1 and the reel stand 1 via the clutch mechanism.

In this way, the reel stand 1 can be operated only by the selective operation of the drive gear.
It is possible to select whether to directly drive or indirectly drive. Next, how these two transmission systems are selected and operated will be described.

FIG. 3 shows the states of the tape fast-forwarding and rewinding operations of the magnetic recording / reproducing apparatus. First, a mode selection mechanism (not shown) is operated to move the drive plate and move the first drive gear 7 to the position shown in FIG. In this state, the idler mechanism meshes with the second drive gear 9, so that the idler mechanism is in the mode for directly transmitting the torque and the rotational speed as described above. Next, the rotation and torque transmitted to the relay gear 15 are
The tape is directly transmitted to the reel stand 1 according to the speed reduction ratio, and the tape is driven with a sufficiently strong force to perform fast forward or rewind operation of the tape.

FIG. 4 shows the state of the braking mode. First, a mode selection mechanism (not shown) moves the drive plate 8,
The first drive gear 7 is moved to the state shown in FIG. In this state, the idler mechanism is moved to the left by the first drive gear 7 and cannot engage with the second drive gear 9.

On the other hand, the first drive gear 7 is also stopped at a position where it does not mesh with the clutch gear 3 provided on the reel base 1, and rotation and torque from the drive source are cut off at the idler mechanism and the first drive gear 7. The reel stand does not rotate.

Next, the braking method of the reel stand 1 after this is the same as the conventional one.

FIG. 5 shows a recording and reproducing mode.

First, a mode selection mechanism (not shown) shifts to the recording / reproducing mode. At this time, the first drive gear moves in the direction of the gear shaft center, which is the direction B in FIG.
Moves the first drive gear 7 to the position shown in FIG.
In this state, the idler mechanism meshes with the first drive gear 7, so that the idler mechanism is in a mode of indirectly transmitting torque and rotation as described above. Next, the rotation and torque transmitted to the relay gear 15 are transmitted to the clutch gear according to the reduction ratio thereof, and then transmitted to the reel stand via the clutch mechanism. This makes it possible to run the tape at a constant speed and wind the tape with a constant torque.

Further, the operation of FIGS. 3 to 5 is also a switching operation when shifting from the direct mode to the indirect mode or vice versa. This is a necessary operation when disengaging a gear that has been meshed once or meshing a gear that is out of mesh again.Driving in a state where gear meshing is abnormal due to interference between gear tips Is to prevent.

Describing the operation of the first drive gear, when trying to engage a gear in a disengaged state by moving it in the direction perpendicular to the rotation center of the gear, immediately before the first tooth tries to engage, The gear is moved with a constant force being applied in the direction in which the gears try to engage with each other (direction B). This force may be a very small force and may be a spring force (not shown) applied to the drive arm. After shifting to the mode, normal meshing is achieved by the rotation of the gear. On the other hand, when trying to remove the meshed gear, on the contrary, the gear is once pulled up in the direction of the rotation center (-B direction) until it is disengaged, and then moved. By these operations, normal meshing can always be maintained.

Although the first drive gear is movable in the embodiment, the second drive gear may be movable. Alternatively, both may be movable.

Further, in the embodiment, for simplification of the description, only one direction of the reel stand is shown, but it is clear that there is the other reel stand around the idler.

EFFECTS OF THE INVENTION As described above, according to the present invention, the operation of the drive gear provided between the idler and the reel stand is selectively performed in the direction of the rotation axis of the gear, thereby simplifying the device. The number of parts can be reduced, and the drive unit can be significantly thinned, which is an excellent effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a reel drive mechanism portion of a magnetic recording / reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view showing a meshed state, and FIGS. Plan view for explaining the operation,
FIG. 6 is a plan view of a reel drive mechanism of a conventional magnetic recording / reproducing apparatus, FIG. 7 is a cross-sectional view showing the meshed state, and FIGS. 8 to 10 are plan views for explaining the operation. 1 ... reel stand, 2 ... clutch felt, 3 ... clutch gear, 4 ... clutch spring, 5 ... stopper gear,
6 ... 1st drive shaft, 7 ... 1st drive gear, 8 ... drive plate, 9 ... 2nd drive gear, 10 ... above idler gear, 11 ... below idler gear, 12 ... idler shaft, 1
3 ... idler arm, 14 ... idler felt, 1
5 ... relay gear, 16 ... idler spring, 17 ... sleeve, 18 ... substrate, 19 ... reel shaft, 20 ... drive shaft, 21 ... idler shaft.

Claims (1)

[Claims] 1. A reel base for mounting a tape, first and second drive gears for driving the reel base, and an idler for driving the reel base via the first or second drive gear. A reel drive mechanism is provided, and at least one of the first and second drive gears is movable in the direction perpendicular to the rotation axis of the drive gear, and one of the first and second drive gears is provided. Is configured to selectively engage with the idler to drive the reel base.