JP3064763B2 - Reel stand brake 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 video tape recorder, a digital audio tape recorder, etc.
The present invention relates to a reel stand brake device.

[0002]

2. Description of the Related Art In recent years, in video tape recorders, digital audio tape recorders, and the like, there has been a strong demand for a reduction in fast-forward / rewind time and a reduction in image output time after fast-forward / rewind. Along with this, the reel speed brake device that brakes the supply / take-up reel table by increasing the tape speed at the time of fast-forward / rewind, or by increasing the tension increase coefficient by fast-forward / rewind while fully loaded into the cylinder. , High braking characteristics are also required.

In the construction of the reel stand brake device, the following two points must be taken into consideration. An example will be described in which the mode is shifted from the fast forward mode to the stop mode. First
Another problem is to prevent tape damage.

When stopping from rapid traverse, a large brake torque (biting torque) is applied to the supply reel table, and a small brake torque (release torque) is applied to the take-up reel table.
It takes. For this reason, the supply reel base tends to stop early, and the take-up reel base tends to stop late. However, when there is more tape on the take-up reel base, the inertia force increases and the tape tension increases. Since the tape runs helically around the inclined post, there is a component force of the tape tension in the vertical direction (axial direction) of the post. When the tension is excessive, the component force also increases, and the tape is pressed against the flange of the guide post. In particular, in the case of a thin tape (180-minute tape), the tape is deformed or damaged due to the low rigidity of the tape.

[0005] Second, tape slack is prevented. When stopping from the fast-forward mode with the supply reel base having more tape and large inertia force, and the take-up reel base having small inertia force, the supply reel base is hard to stop even if a large biting torque is applied. The take-up reel base easily stops even with a small escape torque. For this reason, the tape tends to sag easily. If the tape sags, it will fall off the flange of the guide post and fall. As a result, the next time the tape is wound and stretched, the tape is pressed against the flange of the guide post, causing tape deformation and damage.

As described above, from the beginning to the end of the winding of the tape cassette, tape damage and tape slack are prevented, and the amount of tape flow from receiving a stop command to actually stopping the tape is reduced. In this way, each company proposes the setting of the bite torque and the release torque of the brake torque and the mechanism around the brake.

[0007] In a fast-forward / rewind operation of a general magnetic recording / reproducing apparatus, power is transmitted from a capstan motor for driving a capstan to a reel base, and the tape is wound on the reel base. In such a configuration,
When shifting from the rewind mode to the stop mode, the inertia of the capstan motor is transmitted to the reel base, so that the actual inertia of the take-up reel base is increased, so that tape damage is likely to occur or tape damage may occur. The flow of the pump becomes large.

As means for solving such a problem, there has been proposed a configuration in which the connection between the capstan motor and the reel base is forcibly disconnected in a stop mode as disclosed in Japanese Utility Model Laid-Open No. 02-8277, for example. . FIG. 7 is a plan view of a main part around a reel stand of a conventional example. To briefly explain the configuration,
When the brake member 100 operates in the stop mode, the contact portion 101 of the brake member 100 comes into contact with the swing gear 103 rotatably provided on the rotating arm 102, and separates the swing gear 103 from the reel base 104, and the capstan The power of a motor (not shown) is separated from the reel base 104.

Next, the operation will be described. If a stop command is issued during high-speed running (fast-forward operation), the capstan motor drive is immediately cut, so that the tape tension during running gradually decreases. (FIG. 6) Until the brake member 100 is applied to the reel base 104 and stops, the braking force of the escape torque and the load due to the tape tension act to stop the reel base 104, but the tape tension is low. The load for stopping the reel base 104 is small, and the reel base 104 has a considerable inertial force (rotational energy).

[0010] Therefore, even if a torque is applied to a supply reel table (not shown) and the supply reel table stops immediately, the tape tension increases due to the inertia force (rotational energy) of the reel table 104 (see FIG. 1). 6) Tape damage occurs.

[0011]

As described above, according to the conventional configuration, when the mode is shifted from the fast-forward mode to the stop mode, the tape tension is instantaneously increased, and the tape is damaged. . In particular, the tendency is remarkable when a relatively long time is required for the brake operation (several hundred milliseconds) without using a solenoid or the like for the brake operation or when the inertia moment of the capstan motor is small.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a reel stand brake device according to the present invention has an engaging portion for engaging with a tape reel, and a pair of supply / winding units integrally provided with a gear unit. A take-up reel base, a pendulum gear that selectively meshes with one of the gear portions of the pair of supply / take-up reel bases, a first motor that drives the supply / take-up reel base via the pendulum gear, A mode switching member that moves according to each operation mode, a second motor that drives the mode switching member, a reel brake that substantially simultaneously brakes the pair of supply / take-up reel bases in conjunction with the mode switching member, In conjunction with the switching member, a release member for releasing the engagement between the pendulum gear and the gear portion of the supply / rewind reel base substantially simultaneously with the braking of the reel brake, and a transition from the fast-forward / rewind mode to the stop mode Do In, until meshing with at least pendulum gear and the supply / take-up reel base gear portion is released, the first
And a control circuit that keeps driving the motor.

[0013]

According to the present invention, when the stop command is issued during the rapid traverse operation, the present invention controls until the brake operates.
The tape tension does not drop because the first motor continues to be driven by the circuit . A predetermined tape tension and relief torque operate on the take-up reel base while the brake is operating, and the take-up reel base has less inertial force (rotational energy). Become. At this time, the inertia force of the first motor is separated from the reel base by the release member, so that the inertia force of the take-up reel base is further reduced. For this reason, even if the biting torque operates on the supply reel table, the tape tension does not become extremely high, and the occurrence of tape damage can be prevented.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a timing chart of a transition from a fast-forward mode to a stop mode of the reel stand brake device of the present invention, FIG. 2 is a plan view of the reel stand brake device, FIG. FIG. 5 is an explanatory diagram showing an operation of the reel base brake device in which a transition from a fast-forward / rewind mode to a stop mode is performed, in which main parts are extracted. FIG. 5 is a schematic block diagram in which a capstan motor and a mode motor are driven. .

First, the overall configuration will be described with reference to FIG.
A belt 2 for transmitting a driving force is wound around a capstan motor 1 and a center gear 3 which are driving sources. One end of a pendulum arm 4 is rotatably supported on the center gear 3, and the pendulum gear 5 is rotatably supported on the other end about a pendulum gear shaft 5a.

A PLAY gear arm 15 is provided rotatably about the axes of the take-up reel base 7 and the supply reel base 14, and a PLAY gear 16 is rotatably supported on a PLAY gear shaft 15a provided at one end thereof. doing. PLAY
The gear arm 15 is provided with a regulation pin receiving portion 15b that engages with a regulation pin 17 fixed to a chassis (not shown). The PLAY gear shaft 15a has a regulating arm 1 attached thereto.
9 are engaged with the guide groove 19a, and the follower pin 19b of the regulating arm 19 is engaged with the arm cam surface 8d of the main rod 8. A movement guide groove 19c is formed in the regulating arm 19, and a guide pin 18 provided in the chassis 18 is provided.
Guided and supported by a.

Small gear 5c of center gear 3 and pendulum gear 5
Are always meshed, and the pendulum gear 5 is the capstan motor 1
Is rotatable left and right depending on the direction of rotation of. FF
The idler gear 6 is rotatable around an axis fixed to the chassis, and the take-up reel gear 7a or the supply reel gear 14a is always meshed. PLAY gear 1
6 and the winding limiter gear 7b or the supply limiter gear 14b are always meshed. A take-up tape reel (not shown) is provided on the take-up reel table 7 integrally formed with the take-up reel gear 7a, and a supply-side tape reel (not shown) is provided on the supply reel table 14 formed integrally with the supply reel gear 14a. ) Are engaged. 2 (fast-forward /
In the rewind mode), the output of the capstan motor 1 is the center gear 3, the small gear 5c of the swing gear 5, the large gear 5b,
It is transmitted to the take-up reel base 7 via the FF idler gear 6 and the take-up reel base gear 7a. When the PLAY gear arm 15 rotates (not shown), the output of the capstan motor 1 is the center gear 3 and the small gear 5 of the swing gear 5.
c, transmitted to the take-up reel base 7 via the PLAY gear 16 and the take-up limiter gear 7b. Although not shown, a torque limiter is provided between the take-up limiter gear and the take-up reel base.

From the mode motor 20 to the main cam gear 21
Up to this, a gear train 22 is configured. Main cam gear 2
1 is engaged with a cam pin 23a provided at one end of the main cam lever 23, and a rod pin 23b provided at the other end is a main rod which is a mode switching rod which moves left and right when the mode is changed. 8 guide grooves 8c are engaged. The main rod 8 has a lever cam surface 8a and a brake cam surface 8b.

The take-up brake 11 and the supply brake 12 are pivotally supported near the take-up reel base 7 and the supply reel base 13, respectively.
The brake pin 13 is pulled toward each other by the brake spring 13 bridged between 1b and 12b, and the winding-side brake pin 11a and the supply-side brake pin 12a are in contact with the main rod 8.

A spring engaging portion 9b is provided at one end of a pair of regulating levers 9 having a rotation support shaft, and a regulating lever spring 10 is suspended between the two to draw each other.
The regulating lever 9 is provided with a lever pin 9a. The restricting lever 9 is supported at a position where it can contact the pendulum gear shaft 5a protruding from the pendulum gear 5, as shown in FIG.

As shown in FIG. 5, the mode command detected by the mode detection circuit 50 is transmitted to a capstan motor control circuit 51, and a capstan motor drive circuit 52
Drives the capstan motor 1. Similarly, the mode command detected by the mode detection circuit 50 is transmitted to the mode motor control circuit 53, and the mode motor drive circuit 54 drives the mode motor 20.

The operation of the reel base device configured as described above will be described below. The present invention has a feature in the operation when shifting from the fast-forward / rewind mode to the stop mode, and therefore only the operation will be described. The operation of shifting from the fast-forward mode to the stop mode and the operation of shifting from the rewind mode to the stop mode are basically the same. Therefore, only the operation of shifting from the fast-forward mode to the stop mode will be described. As shown in FIG. 1, even if a stop command is issued during the fast-forward mode, the capstan motor control circuit 51 does not immediately issue a stop command. Drive is continued during time T0. On the other hand, when the mode motor 20 issues a stop command, the mode motor control circuit 53 immediately issues a stop command, so that the mode motor 20 starts to rotate immediately and the main rod 8 through the gear train 22, the main cam gear 21, and the main cam lever 23. To move. When the main rod 8 moves from FIG. 4a to FIG. 4b, the brake pins 1 provided on the respective brakes
Since 1a and 12a come off the cam surface 8b of the main rod 8, the respective brakes start to hit the take-up reel table and the supply reel table. (FIG. 4b) At substantially the same timing, the regulating lever pin 9a is moved to the cam surface 8a of the main rod 8.
, The regulating lever 9 rotates and the swinging gear 5
From the take-up reel base 7 forcibly. Thereafter, the respective brakes operate to work to stop the take-up reel table 7 and the supply reel table 14. (FIG. 4c) Next, the capstan motor 1 is stopped by the control circuit.

On the other hand, looking at the tape tension according to the above-mentioned operation (FIG. 1), the capstan motor 1 continues to be driven even if a stop command is issued, so that the tension in the fast-forward mode is maintained. When the brake is applied, the rotational energy of the take-up reel base 7 is rapidly reduced because the tape tension is not lowered, and the tension is slightly increased. Can be. Therefore, it is possible to shift from the fast-forward mode to the stop mode without causing tape damage. By appropriately selecting the time T0 from when the stop command is issued to when the driving of the capstan motor 1 is stopped, even if there is a difference in inertia of the capstan motor or a load variation of the traveling system, the above-mentioned contents are obtained. Can be achieved.

[0024]

As described above, according to this embodiment, at the time of shifting from the fast-forward / rewind mode to the stop mode, at least the engagement between the pendulum gear and the gear portion of the supply / take-up reel stand is released. Until the capstan motor continues to be driven, the tension before the brake operation is kept high, so that the rotational energy of the take-up reel is gradually consumed by the brake and tape tension. The tape tension can be kept low, and the occurrence of tape damage can be suppressed.
Also, because the swing gear is forcibly separated from the reel base, tape damage can be suppressed regardless of the magnitude of the inertia moment of the capstan motor,
Its practical effect is great.

[Brief description of the drawings]

FIG. 1 is a diagram showing an operation timing chart of a reel stand brake device according to an embodiment of the present invention.

FIG. 2 is a plan view of a reel stand brake device according to an embodiment of the present invention.

FIG. 3 is a side view of a main part of the reel stand brake device according to the embodiment of the present invention.

FIG. 4a is an explanatory diagram of an operation of a reel stand brake device according to an embodiment of the present invention. FIG. 4b is an explanatory diagram of an operation of the reel stand brake device. FIG. 4c is an explanatory diagram of an operation of the reel stand brake device.

FIG. 5 is a schematic block diagram according to an embodiment of the present invention.

FIG. 6 is a diagram showing an operation timing chart of a reel stand brake device in a conventional example.

FIG. 7 is a plan view of a main part of a reel base brake device in a conventional example.

[Explanation of symbols]

 Reference Signs List 1 capstan motor 3 center gear 4 pendulum arm 5 pendulum gear 6 FF idler gear 7 take-up reel base 7a take-up reel gear 8 main rod 8a lever cam surface 8b brake cam surface 9 regulating lever 10 regulating lever spring 11 winding side brake 11a winding side Brake pin 12 Supply side brake 12a Supply side brake pin 13 Brake spring 14 Supply reel base 14a Supply reel gear 50 Mode detection circuit 51 Capstan motor control circuit 52 Capstan motor drive circuit 53 Mode motor control circuit 54 Mode motor drive circuit

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Katsutoshi Nagao 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-64-10451 (JP, A) 170132 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 15/22 G11B 15/18

Claims (1)

(57) [Claims] An engaging portion for engaging the tape reel;
A pair of supply / take-up reel bases integrally provided with a gear unit, a pendulum gear selectively meshing with one of the gear units of the pair of supply / take-up reel bases, A first motor that drives the supply / take-up reel base; a mode switching member that moves in accordance with each operation mode; a second motor that drives the mode switching member; A reel brake that brakes the supply / take-up reel base substantially simultaneously; and a gear between the pendulum gear and the gear portion of the supply / take-up reel base substantially simultaneously with the braking of the reel brake in conjunction with the mode switching member. A release member for releasing the engagement, and the first motor until at least the engagement between the pendulum gear and the gear portion of the supply / take-up reel base is released when shifting from the fast-forward / rewind mode to the stop mode. And a control circuit for continuously driving the reel stand brake device.