JPH09198743A - Braking device for magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of components by maintaining a released condition of braking by making a trigger installed on the brake arm abut against the shaft and instantaneously braking the reel stand by releasing the abutment. SOLUTION: A spring 11 is energized to bring braking arms 9, 10 into pressure-contact with reel stands 21, 22 for braking. A driving motor 1 is rotated to move a slider 31 through a main gear 30 and a gear 30a and the cam section 31d of the slider 31 pushes the protrusion section 9a of the brake arm 9 to release the braking action of the reel stands 21, 22. When the above push is released by the shift of the slider 31 in the direction reverse to the above one, the trigger 32 of the braking arm 10 abutts against the shaft 2a to maintain the released condition of the above braking and forward the magnetic tape. The above abutment is released by a stop action and the braking arms 9, 10 are brought into instantaneous pressure-contact with the reel stands 21, 22 to brake the reel stands.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device of a magnetic recording / reproducing apparatus (including a reproduction-only machine) having a brake arm for braking a reel stand on which a magnetic tape runs.

[0002]

2. Description of the Related Art FIGS. 7 to 10 show a brake device of a conventional magnetic recording / reproducing apparatus of this type. FIG.
A plan view showing F / REWIND (brake release state in the case of fast forward or rewind), FIG. 8 is FF / REW
FIG. 9 is a plan view showing a state in which the drive motor reversely rotates from the IND mode and the trigger is kicked, FIG. 9 is a plan view showing a reset mode (brake state), and FIG. 10 is an exploded perspective view in which an essential part is enlarged. In these figures, 1 is a drive motor, 2 is a worm gear fixed to the output shaft of the drive motor 1, 3 is installed near the end of the worm gear 2, and a torsion spring 4 mounted on the output shaft of the drive motor 1 is a drive motor. The blades 5 loosely fitted to the output shaft of the motor 1 and engaged with the torsion spring 3 are thrust receivers that prevent the blade 4 from falling off the output shaft of the drive motor 1.

The above-mentioned torsion spring 3 is a drive motor 1
In a predetermined one-way rotation of, for example, the rotation of the arrow 1b in the figure, a closing operation is performed in close contact with the output shaft of the drive motor 1,
Along with this, the blades 4 rotate integrally with the rotation of the drive motor 1. In addition, when the drive motor 1 is rotated in the direction of arrow 1a in the figure, the torsion spring 3 performs an opening operation in which the contact with the output shaft of the drive motor 1 is released, and the blades 4 output the output of the drive motor 1 accordingly. The sliding motion is possible relative to the shaft. That is, the torsion spring 3 and the blade 4 constitute a one-way mechanism that rotates integrally with the rotation of the drive motor 1 only when the drive motor 1 rotates in a predetermined direction. Such one-way mechanism is well known.

Further, in FIG. 7 and the like, 6 is a reduction gear which works in conjunction with the worm gear 2, and is rotatably mounted on a shaft 20a provided on a chassis 20 forming the main body of this magnetic recording / reproducing apparatus and meshes with the worm gear 2. It comprises a worm wheel 6b and a gear 6a provided integrally with the worm wheel 6b. 7 is a gear 6a of the reduction gear 6
A main cam gear that meshes with a shaft 20b provided on the chassis 20 and is rotatably mounted on the upper surface of which a cam groove 7a is formed.

Reference numerals 21 and 22 shown in FIG. 7 and the like are reel stands on which a magnetic tape (not shown) is run. Brake arms 9 and 10 respectively brake the reel bases 21 and 22, and are rotatably mounted on shafts 20d and 20e provided on the chassis 20, respectively. These brake arms 9,
10 are connected to each other by a spring 11. In addition,
The brake arm 9 is provided with a protrusion 9a that hangs downward. Reference numeral 13 is a rotation direction for braking the above-mentioned brake arms 9 and 10 on the reel stands 21 and 22, and the reel stand 2
This is a slider for selectively operating the motors 1 and 22 in the rotation direction without braking. The slider 13 has a cam 13c on the upper surface that engages with the protrusion 9a provided on the brake arm 9 described above, and guide pins 20g of the pair of sliders 13 provided on the chassis 20 are relatively loosely fitted to each other. It has a long hole 13b.

A spring 15 has one end connected to the chassis 20 and the other end connected to the slider 13. Reference numeral 12 is a trigger rotatably mounted on a shaft 13a provided on the slider 13, and when the slider 13 is slid against the tensile force of the spring 15, the blade 4 forming the above-mentioned one-way mechanism.
Can be engaged. As shown in FIG. 10, the trigger 12 is provided with a protrusion 12a that hangs downward. Reference numeral 16 denotes a spring, one end of which is connected to the slider 13 and the other end of which is connected to the trigger 12.
2 is urged in the rotation direction to bring the blade 4 closer to the central portion of the blade 4. As shown in FIG. 10, the slider 13 described above is used.
The end surface of the cam 13c of FIG.
A stopper 13d for restricting the rotation of the blade 4 toward the central portion due to the force of the above-mentioned spring 16 is configured.

Reference numeral 8 denotes a brake lever, and a hole 8c formed in the brake lever 8 has a shaft 2 provided in the chassis 20.
It is rotatable by being inserted into 0c.
As shown in FIG. 10, the brake lever 8 is provided with a pin 8a which is loosely fitted in the cam groove 7a of the main cam gear 7 described above on the left side portion in the drawing, and is provided on the trigger 12 described above in the lower portion in the drawing. The inverted L-shaped protrusion 8b engageable with the protrusion 12a is provided. Further, as shown in FIG. 10 and the like, a stopper 20f that restricts the return movement of the slider 13 due to the force of the spring 15 is formed integrally with the chassis 20, and the stopper 20f has a contact portion with the slider 13. A cushioning material 14 is attached to absorb the impact sound when the slider 13 abuts.

The operation of the prior art thus configured is as follows. For example, when in the reset mode (brake state) shown in FIG. 9, the brake shoes of the brake arms 9 and 10 come into contact with the peripheral surfaces of the reel bases 21 and 22 and engage with the protrusions 9 a of the brake arm 9 c 13 c. The end portion of the slider 13 provided with abuts against the cushioning material 14 provided on the stopper 20f by the force of the spring 15,
The trigger 12 on the slider 13 contacts the stopper 13d formed on the end surface of the cam 13c by the force of the spring 16, and the protrusion 12a of the trigger 12 is protruded 8b of the brake lever 8.
(Not engaged), the tip of the trigger 12 is not engaged with the blade 4.

When the drive motor 1 rotates in the direction of arrow 1a in FIG. 10 from this state, the worm gear 2 rotates in the same direction, the reduction gear 6 rotates clockwise in FIG. 9, and the main cam gear 7 passes through the gear 6a. Rotates counterclockwise. Along with this, the brake lever 8 rotates clockwise in FIG. 9 via the pin 8a engaged with the cam groove 7a of the main cam gear 7, and engages with the protrusion 8b of the brake lever 8 to trigger. The protrusion 12a of 12 moves in the direction of arrow 13e in FIG. 9, the slider 13 moves integrally with it in the direction of arrow 13e, and the cam 13c of the slider 13 pushes the brake arm 9 against the force of the spring 11. Then, the brake arm 9 is rotated in the clockwise direction in FIG. 9, and the brake arm 10 is also rotated in the counterclockwise direction in cooperation with the brake arm 9 to release the braking on the reel bases 21 and 22.

From this state, the main cam gear 7 further rotates, the brake lever 8 rotates clockwise, and the trigger 1
When the slider 2 and the slider 13 move further in the direction of the arrow 13e, the tip of the trigger 12 engages with the blade 4. This feather 4
As described above, the rotation direction of is the direction of arrow 1a in FIG. 10, and the rotation of the blade 4 tends to urge the trigger 12 in the direction of arrow 12b in FIG. 13 is engaged with the cam 13c,
This keeps it unrotatable. Therefore, the blades 12 are stopped from rotating by the trigger 12, the torsion springs 3 engaged with the blades 4 are opened, and the blades 4 are opened.
Is in a state of relatively slipping on the output shaft of the drive motor 1. When the position of the trigger 12 reaches a predetermined position, the shift to the FF / REWIND mode is completed, a mode switch (not shown) is activated, and the drive motor 1 is stopped by the signal. FIG. 7 shows the state at this time. As a result, the magnetic tape (not shown) mounted on the reel stands 21 and 22 can run at high speed.

When the FF / REWIND mode shown in FIG. 7 is released, the drive motor 1 is rotated in the direction opposite to the above-described direction of rotation, that is, the direction indicated by the arrow 1b in FIG. At this time, the rotation direction of the drive motor 1 coincides with the closing direction of the torsion spring 3, and the blades 4 rotate together with the output shaft of the drive motor 1, while the blades 4 do not rotate once, that is, instantaneously. Then, the tip of the trigger 12 is kicked by the blade 4 in the direction indicated by the arrow 12c in FIG. As a result, the trigger 12 rotates, and the protrusion 12a of the trigger 12 and the protrusion 8b of the brake lever 8 are disengaged from each other in the horizontal direction in the drawing, and the force of the spring 15 causes the slider 13 to move in the direction of arrow 13f in FIG. Sliding, the slider 13 collides with the cushioning material 14 of the stopper 20f, and
The brake arm 9 moves counterclockwise, and the brake arm 10
Rotate clockwise, and instantly reel stand 2
The brake shoes come into contact with Nos. 1 and 22 to enter a braking state. The state at this time is as shown in FIG.

In the state shown in FIG. 8, the protrusion 12a of the trigger 12 is located above the protrusion 8b of the brake lever 8 in the figure. When the drive motor 1 continues to rotate in the direction of the arrow 1b in FIG. 10 from such an intermediate state, the main cam gear 7 moves through the worm gear 2 and the reduction gear 6 in FIG.
8 in the direction of arrow 7c, that is, in the clockwise direction in FIG. 8, the brake lever 8 rotates in the counterclockwise direction in FIG. 8 via the pin 8a engaged with the cam groove 7a. While the brake lever 8 rotates to a predetermined position, the protrusion 8b of the brake lever 8
The trigger 12 is disengaged from the protrusion 12a of the trigger 12 in the upward direction in the drawing, and the force of the spring 16 causes the trigger 12 to rotate counterclockwise in FIG. 8 to hit the stopper 13d of the cam 13c of the slider 13 and stop. This state is detected by the mode switch, and the drive motor 1 is stopped by the signal. As a result, the reset mode (brake state) shown in FIG. 9 is entered.

[0013]

DISCLOSURE OF THE INVENTION In a conventional magnetic recording / reproducing apparatus braking device having the above-described structure,
Brake arms 9, 10 for braking the reel stands 21, 22
13 for rotating the FF / REWIND mode (brake release state) or reset mode (brake state), the spring 1 for driving this slider 13
5, a spring 16 for rotating the trigger 12, and a slider 1
Since it is necessary to provide the cushioning material 14 that absorbs the impact sound at the time of abutting the contact point 3, the torsion spring 3, the blade 4, the thrust receiver 5 and the like that constitute the one-way mechanism, the number of parts becomes very large. However, the structure is complicated and the assembly is not easy. Along with this, there are problems that the production cost becomes high and the parts management becomes complicated.

When the slider 13 comes into contact with the stopper 20f, the impact sound is still offensive although the cushioning material 14 is present. The present invention has been made in view of the above-mentioned conventional circumstances, and a first object of the present invention is to provide a brake device for a magnetic recording / reproducing apparatus, which has a small number of parts, has a simple structure, and is easy to assemble. Especially. A second object is to provide a braking device for a magnetic recording / reproducing apparatus which can eliminate an impact sound such as an impact sound generated when a slider abuts a stopper, in addition to the first object. .

[0015]

In order to solve the above problems and achieve the first object, a brake device for a magnetic recording / reproducing apparatus according to the present invention as set forth in claim 1 runs a magnetic tape. In a braking device of a magnetic recording / reproducing apparatus having a brake arm for braking a reel stand, the brake arm is movably provided with respect to a chassis forming a main body of the magnetic recording / reproducing apparatus, and the brake arm is rotated for braking the reel stand. Direction, and a movable member that selectively actuates the reel base in a rotation direction that does not brake, drive means that drives the movable member, and a movable member in a rotation direction that brakes the brake arm to the reel base. Even when it works
The holding means holds the reel base so as not to brake the reel base, and the holding release means releases the holding of the brake arm by the holding means. Further, in order to achieve the second object, the present invention according to claim 1 provides a member which collides and produces a sound when the holding by the holding means is released by the holding release means. It is configured without using.

[0016]

According to the invention as set forth in claim 1, which is configured as described above, when the movable member is actuated and the brake arm is rotated in a rotation direction in which the reel base is not braked, the movable member is interposed. The brake arm does not brake the reel base, and is kept in a predetermined reset mode (first brake released state).
When the movable member is operated from the reset mode to rotate the brake arm in a rotation direction for braking the reel base, the holding means is operated to hold the brake arm so as not to brake the reel base. The predetermined FF / REWIND mode (second brake release state) is maintained. further,
When the holding release means operates from this FF / REWIND mode and the holding of the brake arm by the holding means is released, the brake arm rotates in the rotation direction for braking the reel base, and enters the braking state. Further, the movable member is actuated from this state, the movable member rotates the brake arm in a rotation direction in which the reel base is not braked, and the predetermined reset mode (first brake release state) described above is maintained.

That is, the slider used in the prior art, the spring for driving the slider, the spring for rotating the trigger,
In addition, a cushioning material that absorbs the impact sound when the slider abuts, and a torsion spring, a blade that constitutes a one-way mechanism,
Since components such as a thrust receiver are unnecessary, drive control of the brake arm for braking or releasing the reel base can be realized with a small number of components. Further, since there is no slider itself for generating impact noise, impact noise is not generated.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 is a plan view showing a reset mode (first brake released state), and FIG. 2 is an FF.
FIG. 3 is a plan view showing the / REWIND mode (second brake release state), and FIG. 3 is a plan view showing the state (brake state) in which the drive motor reversely rotates from the FF / REWIND mode and the trigger is released. 4 is a detailed vertical sectional view of the trigger periphery of FIG. 1 viewed from the arrow direction, FIG. 5 is a vertical sectional detailed view of the trigger periphery of FIG. 2 viewed from the arrow direction, and FIG. 6 is an arrow around the trigger periphery of FIG. FIG. 3 is a detailed view of a vertical section viewed from the direction. The same parts as those shown in FIGS. 7 to 10 described above are designated by the same reference numerals.

As shown in these figures, the worm gear 2
And the reduction gear 6 constitute a rotation transmission means for transmitting the rotational force of the drive motor 1 as the rotational force of the main gear 30. The worm gear 2 has a shaft 2a that rotates integrally with the worm gear 2 at its end. Reference numeral 31 denotes a slidable slider driven by the main gear 30.
Rack gear 31a that meshes with the gear 30a, chassis 2
Slot 31 that is loosely fitted in the bosses 20h and 20i
b and 31c are provided, and a cam portion 31d that engages with the protrusion 9a of the brake arm 9 is provided. Then, by the cam portion 31d, the brake arms 9, 1
0 is selectively operated in a rotation direction in which the reel bases 21 and 22 are braked and in a rotation direction in which the reel bases 21 and 22 are not braked.

Further, reel stands 21 and 22 for running a magnetic tape (not shown), brake arms 9 and 10 for respectively braking these reel stands 21 and 22, and a spring 11 for connecting these brake arms 9 and 10. The brake arm 9 has a protrusion 9a and an elongated hole 9b.
Is formed. In addition, even when the brake arms 9 and 10 are actuated in the rotation direction for braking the reel bases 21 and 22, the brake arms 9 and 10 are not provided.
Is formed with a pin 10a to which a trigger 32, which is a holding means for holding the reel bases 21 and 22 so as not to brake, is rotatably attached, and a pin 10b that is loosely fitted in the elongated hole 9b of the brake arm 9. .

A resin spring portion 32a is integrally formed with the trigger 32, and the trigger 32 is biased counterclockwise in FIGS. 4 to 6 by the resin spring portion 32a.
The stopper portion 32b formed integrally with the trigger 32 is pressed against the locking portion of the brake arm 10 to hold the trigger 32 at a predetermined position. Further, the shaft 2a formed integrally with the worm gear 2 is a holding release means for releasing the holding of the brake arms 9 and 10 by the trigger 32 which is the holding means described above. Note that 20a to 20
e is a shaft provided on the chassis 20.

The reel stands 21 and 2 in this embodiment
The braking operation and the braking release operation of No. 2 are as follows. For example, in the reset mode (first brake release state) shown in FIG. 1, the brake arm 9 has the protrusion 9a.
Is pushed by the cam portion 31d of the slider 31 and the spring 11
The reel stand 21 is stopped at a position where it is not braked against the force of. Further, the pin 10b of the brake arm 10 is pushed by the wall 9c of the elongated hole 9b of the brake arm 9, so that the brake arm 10 also stops at the position where the reel base 22 is not braked against the force of the spring 11. is there. FIG. 4 is a detailed vertical cross-sectional view of the periphery of the trigger 32 in this state as seen from the direction of the arrow. The trigger 32 is biased in the counterclockwise direction by the integrally formed resin spring portion 32a. , Is locked by the stopper portion 32b. Further, the end portion 32c of the trigger 32 is in a positional relationship apart from the shaft 2a of the worm gear 2.

From this state, the drive motor 1 rotates in the clockwise direction of FIG. 4, the worm gear 2 rotates in the same direction, and when the reduction gear 6 rotates in the clockwise direction of FIG. The main gear 30 rotates counterclockwise.
Along with this, the slider 31 is guided by the bosses 20h and 20i via the rack gear 31a meshing with the gear 30a of the main gear 30 and moves to the right in the drawing, and accordingly, engages with the cam portion 31d. Through the protruding portion 9a, the brake arms 9 and 10 start to rotate in a direction to brake the reel bases 21 and 22. When the slider 31 further moves to the right, the end 32c of the trigger 32 attached to the brake arm 10 contacts the shaft 2a formed integrally with the worm gear 2, and the rotation of the brake arm 10 is stopped. Further, the wall 9d of the elongated hole 9b is pushed by the pin 10b, and the brake arm 9 also stops rotating. When the slider 31 further moves to the right, the cam portion 3 of the slider 31
1d separates from the protrusion 9a of the brake arm 9. When the mode switch (not shown) detects that the position of the slider 31 is at the predetermined position, the drive motor 1 is stopped by the signal.

FIG. 5 is a detailed vertical cross-sectional view of the periphery of the trigger 32 in this state as seen from the direction of the arrow in FIG. 2. The end 32c of the trigger 32 is integrally formed with the worm gear 2 on the shaft 2a. Since the trigger 32 is locked by the stopper portion 32b from being contacted with the drive motor 1 until the rotation of the drive motor 1 is stopped, the end portion 32c and the worm gear 2 are integrally formed. 2a is in a relatively slipping (slipping) state. FIG. 2 shows the FF / REWIND mode (second brake release state) formed by such an operation. At this time, reel stand 2
1, 22 are rotated at high speed in a known manner, and the magnetic tapes (not shown) mounted on these reel stands 21, 22 are run at high speed.

Further, when the FF / REWIND mode (second brake release state) shown in FIG. 2 is released, the drive motor 1 is driven to rotate in a rotation direction opposite to the rotation direction described above. That is, the shaft 2a shown in FIG. 5 rotates counterclockwise. At this time, the trigger 32 in contact with the shaft 2a rotates clockwise against the resin spring 32a by the frictional force received by the end 32c.

The following forces act on the trigger 32 as shown in FIG. That is, the traction force G by the spring 11 received from the pin 10a of the brake arm 10 and, as its reaction force, the force G'received from the shaft 2a and the brake arm 10
From the brake arm 10 by the frictional force μG between the pin 10a of the trigger 32 and the bearing 32d of the trigger 32, the frictional force μ′G ′ between the shaft 2a and the end 32c of the trigger 32, and the resin spring portion 32a of the trigger 32. The received force F acts. This time,
The total moment M for turning the trigger 32 counterclockwise is: M = L × F + r × μG Further, the total moment M ′ for turning the trigger 32 clockwise is M ′ = L ′ × μ′G ′ The relationship between M and M ′ described above is set in advance so as to satisfy M ′> M.

The trigger 32, which has started to rotate clockwise against the resin spring 32a due to the frictional force between the shaft 2a and the end portion 32c of the trigger 32, is
That is, the holding force of the trigger 32 on the brake arm 10 is instantly released by the pulling force of the spring 11, and the brake arm 10 slides to the left above the shaft 2a shown in FIG. 5 together with the brake arm 10, so that the brake arm 10 moves clockwise in FIG. , The brake arm 9 rotates counterclockwise, and the brake shoes instantly come into contact with the peripheral surfaces of the reel bases 21 and 22 to enter a braking state. FIG. 3 shows a braking state formed by such an operation. Even at this point, the slider 31
The cam portion 31d is separated from the protrusion 9a of the brake arm 9. Further, FIG. 6 is a detailed vertical cross-sectional view of the periphery of the trigger 32 in this state as seen from the direction of the arrow, but the trigger 32 is in a state of riding on the shaft 2a.

When the drive motor 1 further rotates in the counterclockwise direction shown in FIG. 6 from this state, the worm gear 2 rotates in the same direction, and accordingly, the reduction gear 6 rotates counterclockwise in FIG. This allows the main gear 3 to pass through the gear 6a.
0 rotates clockwise. Along with this, the main gear 30
The slider 31 is guided to the bosses 20h and 20i via the rack gear 31a meshing with the gear 30a of
Move to the left in the figure. Then, the cam portion 31d of the slider 31 comes into contact with the protrusion 9a of the brake arm 9 and further presses the protrusion 9, and the brake arm 9 rotates against the spring 11 in the clockwise direction shown in FIG. The brake arm 10 is also pushed by the wall 9c of the elongated hole 9b of the brake arm 9 and rotates counterclockwise. That is, the engaging protrusion 9a
Brake arms 9 and 10 are connected to reel stands 21 and 2 via
2 starts rotating in a direction that does not brake.

In FIG. 6, the trigger 32 moves to the right in the figure above the shaft 2a together with the brake arm 10 to move the shaft 2a.
It is pushed away by the resin spring 32a to rotate counterclockwise and is locked by the stopper 32b. When the mode switch (not shown) detects that the position of the slider 31 is at the predetermined position, the drive motor 1 is stopped by the signal. This returns to the reset mode (first brake release state) shown in FIG. 1 described above.

In this embodiment, because of the above-mentioned structure, the slider, the spring for driving the slider, the spring for rotating the trigger, and the slider contact which have been conventionally used as described above. The cushioning material that absorbs the impact sound at the time of contact and the parts such as the torsion spring, blades, and thrust receivers that make up the one-way mechanism are unnecessary, and the drive control of the brake arm that brakes or releases the reel base is unnecessary. It can be realized with a small number of parts, and production costs can be kept low. Further, since there is no slider itself for generating impact noise, impact noise is not generated.

Here, the superiority of this embodiment will be described again by comparing the embodiment of the present invention with the above-mentioned conventional one. Generally, in this type of magnetic recording / reproducing apparatus, when fast-forwarding or rewinding a magnetic tape,
The braking of the reel stand of the two reels around which the magnetic tape is wound is released, and one reel stand is rotated at high speed. By the way, in starting the fast-forwarding or the like, there is no problem even if the rotation of the reel rises slowly. However, when stopping the fast-forwarding magnetic tape, it is desirable to stop the tape instantaneously by the operation.

Therefore, in order to brake the reel base as quickly as possible after the stop operation, the conventional brake device of the magnetic recording / reproducing apparatus is constructed as described with reference to FIGS. 7 to 10. The points of this conventional technique can be explained as follows. That is, the reel stand 21,
A brake arm 9 and 10 having brake shoes pressed against the peripheral surface of 22 by the biasing force of the first spring 11, and a brake lever 8 that is moved according to the rotation of the drive motor 1 as the drive means. A slider 13 having an engaging portion consisting of one movable member and a trigger 12 that can be engaged with the member, and being moved by the movement of the first movable member against the second spring 15. When the magnetic tape being fast-forwarded is stopped by the second movable member, the brake shoe is moved against the first spring 11 by the second movable member. The engagement between the engaging portion and the first movable member is released, whereby the second movable member is moved by the second spring 15, and the brake shoe is biased by the first spring 11. By It is pressed against the reel base 21, 22 the reel base 21, 22 is braked. With this structure, the reel stand 2 is instantly released after the engagement is released.
1, 22 are braked.

The embodiment of the present invention can be described as follows in a form corresponding to this. That is, the brake arms 9 and 10 each having a brake shoe pressed against the peripheral surfaces of the reel bases 21 and 22 by the biasing force of the spring 11, and the slider 31 that is moved in response to the rotation of the drive motor 1 as the drive means. And a contact portion that is provided on the brake arm 10 and includes a trigger 32. The brake arm 1 is moved by the movement of the movable member.
By pressing 0, the brake arm 10 is moved against the spring 11, and when the pressing is released, the contact portion is in a substantially fixed relationship with the chassis.
The reel base 21, which is brought into contact with the fixed portion composed of the shaft 2a,
The state in which the braking of 22 is released is maintained, the magnetic tape is fast forwarded, and the operation of stopping the magnetic tape releases the contact between the contact portion and the fixed portion, and the brake shoe causes the spring 11 to move. By the urging of the reel bases, the peripheral surfaces of the reel bases 21 and 22 are instantly contacted, and the reel bases are braked.

Comparing the conventional one grasped as described above with this embodiment, there are the following differences in the number of parts. Conventionally, two movable members are used, but in the embodiment, one movable member is used.
In the embodiment, the number of springs that has been used in the past is two, and the number of springs that has been used in the past is one. Therefore, in the embodiment, a fixing portion that is not necessary in the past is required. However, by using the shaft 2a as the fixed portion of,
Since it does not increase the number of parts, as described above,
The number of parts in the embodiment is reduced. Further, in this embodiment, the second spring 15 is urged by the second spring 15.
Since no movable member is required, the stopper 20f and the cushioning material 14 are unnecessary.

Further, comparing the conventional one grasped as described above with this embodiment, the conventional one uses "engagement", and the embodiment of the present invention uses "contact". The points are different. It cannot be said unconditionally which structure is simple, the structure for this engagement and the structure for releasing it, and the structure for the contact and the structure for releasing it. "Release" by reverse rotation of motor 1
If so, the configuration in the case of "abutting" becomes simpler as described below.

That is, in this embodiment, the drive motor 1 in a fixed relationship with the chassis 20 is rotated by the drive motor 1 as a structure related to the "contact" and the "release". To be able to contact the peripheral surface of the shaft 2a,
A trigger 32 that is rotatably attached to the brake arm 10, has its rotation position determined in one rotation direction with respect to the brake arm, and is biased to be positioned at this rotation position. When the magnetic tape is fast-forwarded, the trigger 32 is brought into contact with the peripheral surface of the shaft 2a, and the trigger receives a force in the direction in which the rotational position is determined, and the contact state is maintained. Then, when the braking of the reel bases 21 and 22 is released and the rotation direction of the drive motor 1 is reversed as described above, the trigger 32 is rotated against the above-mentioned urging, and the contact is made. It is configured to come off.

On the other hand, in the above-mentioned conventional one,
As a configuration related to the “engagement” and the “release”, the drive motor 1 that is in a fixed relationship with the chassis 20 and the trigger 12 that is engageable with the first movable member are the second It has a trigger 12 which is rotatably attached to the movable member, has its rotational position defined in one rotational direction with respect to the second movable member, and is biased to this rotational position. Further, a blade 4 forming a one-way mechanism is attached to the output shaft of the drive motor 1. When the magnetic tape is fast-forwarded, the first movable member and the second movable member are engaged with each other via the engaging portion, and the blade 4 is rotated via the torsion spring 3 constituting the one-way mechanism. Since this is not done, this engagement state is maintained and the braking of the reel base is released as described above. When the rotation direction of the drive motor 1 is reversed, the blade 4 rotates, and the trigger 12 is kicked by the blade 4 and rotated,
The engagement is configured to be disengaged.

Therefore, in the embodiment of the present invention,
At least the conventional "one-way mechanism including blades" is unnecessary, and the number of parts is reduced accordingly. In the above description, the resin spring portion 32a is formed integrally with the trigger 32, but instead of the resin spring portion 32a,
The trigger 32 may be biased by a separate metallic coil spring or the like.

[0039]

Since the present invention is configured as described above, drive control of the brake arm for braking or releasing the reel base can be realized with a small number of parts, and the structure is simple and the assembly is easy. is there. Therefore, a significant cost reduction can be achieved. Furthermore, since there is no member that generates an impact sound, it is possible to provide a brake device for a magnetic recording / reproducing apparatus that does not generate an offensive impact sound.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a reset mode (first brake released state) according to an embodiment of the present invention.

FIG. 2 shows an embodiment of the present invention, and FF
It is a schematic plan view which shows / REWIND mode (2nd brake release state).

FIG. 3 shows an embodiment of the present invention, and FF
FIG. 6 is a schematic plan view showing a state (brake state) in which the drive motor reversely rotates from the / REWIND mode and the trigger is released.

FIG. 4 is a schematic vertical sectional view of an essential part showing a reset mode (first brake released state) according to the embodiment of the present invention.

FIG. 5 shows an embodiment of the present invention, and FF
FIG. 6 is a schematic vertical cross-sectional view of a main part showing a / REWIND mode (second brake released state).

FIG. 6 is a view showing an embodiment of the present invention, and FF
FIG. 6 is a schematic vertical cross-sectional view of a main part showing a state (brake state) in which a drive motor is reversely rotated from a / REWIND mode and a trigger is released.

FIG. 7 shows a conventional example, FF / REWIND
It is a schematic plan view showing a mode (brake release state).
It is.

FIG. 8 shows a conventional example, FF / REWIND
FIG. 7 is a schematic plan view showing a state in which the drive motor is reversed from the mode and the trigger is kicked.

FIG. 9 shows a conventional example and is a schematic plan view showing a reset mode (brake state).

10 is a schematic enlarged perspective view in which a part of the brake device shown in FIG. 7 is disassembled.

[Explanation of symbols]

 1 Drive Motor 2 Worm Gear 2a Shaft 3 Torsion Spring 4 Blade 5 Thrust Receiver 6 Reduction Gear 6a Gear 6b Worm Wheel 7 Main Cam Gear 7a Cam Groove 8 Brake Lever 8a Pin 8b Projection 8c Hole 9, 10 Brake Arm 9a Projection 9b Long Hole 9c, 9d wall 10a pin 10b pin 11 spring 12 trigger 12a protrusion 13 slider 13a shaft 13b oblong hole 13c cam 13d stopper 14 cushioning material 15 and 16 spring 20 chassis 20a to 20e shaft 20f stopper 20g guide pin 20h and 20i boss. , 22 reel stand 30 main gear 30a gear 31 slider 31a rack gear 31b, 31c oblong hole 31d cam part 32 trigger 32a resin spring part 32b stopper part 32c end part 32d bearing part

Claims (11)

[Claims] 1. A braking device for a magnetic recording / reproducing apparatus, comprising a brake arm for braking a reel stand for traveling a magnetic tape, the brake arm being movably provided with respect to a chassis forming a main body of the magnetic recording / reproducing apparatus. A movable member for selectively actuating the movable member in a rotating direction for braking the reel base and a rotating direction for not braking the reel base, a driving unit for driving the movable member, and the movable member for moving the brake arm to the reel. A holding means for holding the reel base so as not to brake the reel base even when it is operated in a rotating direction for braking the base, and a holding release means for releasing the holding of the brake arm by the holding means. A brake device for a magnetic recording / reproducing apparatus, which is characterized in that 2. The movable member is a slider which can be moved substantially horizontally, has a slot extending along the sliding direction, and a pin loosely fitted in the slot is mounted on the chassis. The brake device for a magnetic recording / reproducing apparatus according to claim 1, wherein the brake device is provided. 3. The movable member and the brake arm are connected to each other by engaging a protrusion provided on the brake arm with a cam provided on the movable member. A brake device for the magnetic recording and reproducing device described. 4. The drive means for the movable member includes a main gear having a gear, and the slider has a rack gear meshing with the gear.
Alternatively, the brake device of the magnetic recording / reproducing device according to the item 3. 5. The holding means is constituted by a trigger rotatably provided on a pin formed integrally with one of the brake arms.
5. A brake device for a magnetic recording / reproducing device according to any one of 3 and 4. 6. The trigger is composed of an elastic member,
The brake device of the magnetic recording / reproducing apparatus according to claim 5, wherein the brake device is locked to the brake arm. 7. The brake device for a magnetic recording / reproducing apparatus according to claim 6, wherein the trigger is made of resin. 8. The holding release means comprises a drive motor and a shaft integrally rotated by the drive motor,
When the movable member operates the brake arm in the rotation direction for braking the reel base, the holding means is brought into contact with the shaft, the brake arm holds the reel base so as not to brake, and the drive is performed. 8. The contact between the holding means and the shaft is released only when the motor rotates in a predetermined direction, and the holding means is released from the contact. Brake device for magnetic recording and reproducing device. 9. The brake device for a magnetic recording / reproducing apparatus according to claim 8, further comprising a rotational force transmitting means for transmitting the rotational force of the drive motor to the drive means of the movable member. 10. A brake shoe which is pressed against the peripheral surface of the reel stand by spring bias, a movable member which is moved according to the rotation of a motor as a driving means, and a brake arm provided with the brake shoe. An abutment portion, and by pressing the brake arm by the movement of the movable member, the brake arm is moved against the spring, and when the pressing is released, the abutment portion is connected to the chassis. A state in which the reel base is maintained in a state where the brake is released by being brought into contact with a fixed portion that is in a substantially fixed relationship, and the magnetic tape can be fast forwarded in this state, and the operation of stopping the magnetic tape causes the magnetic tape to stop. The contact between the contact portion and the fixed portion is released, and the brake shoe is instantaneously brought into contact with the peripheral surface of the reel base by the above-mentioned spring bias, and the reel base is braked. A braking device for a magnetic recording / reproducing apparatus, which is configured as described above. 11. The motor, which is in a fixed relationship with a chassis, and is rotatably attached to the brake arm so as to be able to contact the peripheral surface of a shaft that is rotated by the motor and that acts as the fixing portion. A rotation position is defined in one rotation direction with respect to the brake arm, and the trigger acts as the contact portion and is biased to be positioned at this rotation position. In the case of fast-forwarding, etc., the trigger is brought into contact with the peripheral surface of the shaft, and the trigger receives a force in the direction in which the rotational position is determined, and this contact state is maintained.
As described above, when the braking of the reel base is released and the rotation direction of the motor is reversed, the trigger is rotated against the bias and the contact is released. The brake device of the magnetic recording / reproducing apparatus according to claim 10.