JPH03203855A - Magnetic tape recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent a loading load from becoming max. and also to prevent tape tension from becoming excessive by releasing a brake mechanism of a supply reel base before loading poles reach their respective loading positions. CONSTITUTION:A brake inhibiting mechanism 101 is constituted of a slide plate 33, a slide plate 34, a guide pin 43 and a guide groove 11b, while a tension servo mechanism 103 is constituted of a tension arm 32, a brake band 41, a tension pole 33 and a tension spring 42. In this case, a brake upon the supply reel base 12 is inhibited until the loading poles 19, 20, 24 and 25 reach their prescribed positions (loading completion positions) by the brake inhibiting mechanism 101. By this method, driving load of pole bases is prevented from increasing, while the magnetic tape tension is not in excess, and the magnetic tape is prevented from flawing as well.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic tape recording/reproducing apparatus such as a video tape recorder (VTR), and more particularly to a structure for adjusting the tension of a magnetic tape during loading.

(Prior Art) As is well known, a VTR performs recording and reproduction by winding a magnetic tape over a predetermined angle range around a drum having a rotating magnetic head. Such a VTR has a loading pole that is set up on a ball base that moves along a predetermined trajectory, and when loading a tape cassette, etc., the ball base is positioned at one end of the trajectory (unloading position), and the ball base is positioned at one end of the trajectory (unloading position) to perform playback or playback. When the recording operation button is operated, the pole base is moved toward the other end of the trajectory (loading completion position), and loading is performed by pulling out the tape with the loading pole and winding it around the drum. During playback or recording, the tension pole provided at the tip of the tension arm is urged by a tension spring to contact the tape, and the brake band connected to the tension arm is hung on the supply reel stand. Rotate the tension arm to brake the supply reel stand and adjust the tape tension.

Conventionally, in such a VTR, a tension arm is swingably supported near the unloading position on the trajectory of the ball base, and during unloading, etc., the tension arm is brought into contact with the ball base at the unloading position. , the tension pole is held in a position corresponding to the notch of the cassette, and the tension arm is held in a non-braking state that does not apply braking force to the supply reel stand, and the ball base moves from the unloading position due to the loading operation and the ball It was configured so that when the base is separated from the tension arm, the tension arm moves to a braking enabled state in eight rows in which it can apply braking force to the supply reel stand.

The above-mentioned conventional VTR is known from Japanese Patent Application Laid-Open No. 83-225981.

(Problem to be Solved by the Invention) However, in the above-mentioned VTR, before the ball base reaches the loading completion position, the ball base moves away from the unloading position and the tension arm shifts to a brakeable state. Braking force will be applied to the supply reel stand before the loading operation is completed, causing an increase in the drive load on the ball base, and the tape may be damaged due to increased tape tension during the loading operation. There was a problem.

The present invention has been made in view of the above problems, and provides a magnetic tape recording/reproducing device that prohibits the tension arm from shifting to a brakeable state until the loading operation is completed, and the present invention provides a magnetic tape recording/reproducing device that prevents the tension arm from shifting to a brakeable state until the loading operation is completed. The purpose is to reduce the driving load and also to prevent damage to the tape due to an increase in tape tension.

(Means for Solving the Problems) A magnetic tape recording/reproducing device of the present invention moves along a predetermined trajectory to pull out a magnetic tape suspended between a supply reel and a take-up reel in a cassette. A loading pole that winds the magnetic tape at a predetermined position around a drum equipped with a rotating magnetic head over a predetermined angle range, and a tension pole provided at the tip of a swingably supported tension arm are biased by a tension spring. A brake band that is in contact with the Fa magnetic tape and connected to the tension arm is wound around the supply reel stand, and this brake band tightens the supply reel stand in response to the swinging of the tension arm and applies braking force to the co-feed reel stand. According to the present invention, the magnetic tape may include a tension servo mechanism that adjusts the tension of the magnetic tape, and a braking prohibition mechanism that prohibits the tension servo mechanism from braking the supply reel stand until the loading pole reaches the predetermined position. This is the gist.

(Function) The magnetic tape recording/reproducing apparatus of the present invention prevents the supply reel stand from braking until the loading pole reaches a predetermined position (loading completion position), thereby preventing an increase in the driving load of the ball base. Therefore, the tension on the magnetic tape does not become excessive, and damage to the magnetic tape can be prevented.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

1 to 8 show a magnetic tape recording/reproducing apparatus according to an embodiment of the present invention, and FIGS. 1, 2, 3, and 4 are plan views of main parts in different states, and FIG. 5 is a perspective view of the main parts, FIG. 6 is a plan view of the main parts of -, FIG. 7 is a plan view of other main parts of -, and FIG. 8 is a schematic diagram of the tape running system.

In FIG. 8, 11 is a main chassis, and a supply reel stand 12 and a take-up reel driving gear 13 are rotatably arranged side by side in the lower part of the chassis 11, and a cassette is installed above this lower part. A cassette housing (not shown) to be loaded is supported so as to be movable up and down. Supply reel stand 1
2 and the take-up reel drive gear 13 are connected to a capstan motor (not shown) and driven integrally with the capstan, which will be described later. As is well known, a cassette is housed in a case (not shown) with a magnetic tape 16 wound between a supply reel 14 and a take-up reel 15, and the supply reel 14 is supplied when the cassette housing is lowered. The take-up reel is on the reel stand 12! The outer peripheral gear of the lower flange 5 meshes with the take-up reel driving gear 13. Note that 17 is a guide ball provided in the case of the cassette.

Further, a drum 18 is supported on the upper part of the chassis 11 in the drawing, and a loading guide ball 19, a loading inclined ball 20, an impedance roller 21, an inclined ball 22, and a tension pole 23 (described later) are mounted on the left side of the drum 18 in the drawing. Loading guide ball 24, loading tilt ball 25, tilt ball 26, middle ball 27, A/C head 28, guide roller 29, pinch roller 30, and capstan 3 are on the right side in the figure of 18.
1 is placed. The drum 18 consists of a lower drum fixed to the chassis 11 and an upper drum provided with a magnetic head, and the upper drum is driven and rotated by a drum motor. The loading guide ball 19 and the loading inclined ball 20 are supported by a ball base (not shown), and similarly, the loading guide ball 24
The loading tilt ball 25 is also supported by a pole base, and these pole bases are supported so as to be movable along a predetermined trajectory and are driven by a mode control motor (not shown). These loading poles 19.20.2
4.25C and below, collectively referred to by the symbol LP) move upward in a predetermined trajectory in the figure during loading, pull out the magnetic tape 16 from the cassette, and touch the drum 18 at a predetermined angle at the loading completion position at the upper end of the trajectory in the figure. (see Figure 8), and during unloading, the magnetic tape 1 moves in the opposite direction to the loading time.
6 is stored in the cassette.

Note that the drum 18, impedance roller 21, inclined balls 22, 26, middle ball 27, A/C head 28
, the guide roller 29, the pinch roller 30, and the capstan 31 will not be described.

As shown in FIGS. 1 to 4, the tension pole 23 is erected at the tip of the tension arm 32, and the base end of the tension arm 32 is swingably supported by the slide plate 33. A slide plate 331 is supported on the upper surface of the chassis 11 so as to be slidable in the vertical direction in the figure.
As shown in the figure, a limit plate 34 is slidably provided on a slide plate 33. As shown in detail in FIG. 7, the slide plate 33 has guide elongated holes 33a and 33b extending vertically in the lower part and the center part of the figure, respectively, and the elongated hole in the center part of the figure. 33b, a locking hole 33c is formed in the upper part of the figure, a long hole 33d extending vertically is formed in the lower part of the figure, a spring locking part 33e1, a cam face 33f, and a stepped engagement part 33g are formed. , a support pin 35 is erected close to the upper edge of the elongated portion 33a. The slide plate 33 has a long hole 33a.

Guide pin 36 erected on the upper surface of the chassis 11 at 33b
a, 36b are slidably inserted, a drive pin 37a provided on a drive lever 37, which will be described later, is loosely inserted into the locking hole 33c, and its lower end in the figure is engaged with the lower edge of the elongated hole 33d in the figure. A stopped spring 38 is arranged. This slide plate 33 is driven by the swinging of the drive lever 37, and guides the guide bin 36a within the elongated plates 33a and 33b.

36b slides and moves in the vertical direction in the figure. As will be described later, the drive lever 37 is driven by the mode control motor described above in synchronization with the loading pole LP, and the slide plate 33 is driven by the loading pole L.
It is located at the uppermost position in the figure (see FIGS. 3 and 4) at the loading completion position of P.

Although not shown clearly in the figure, a pin of the plate slides on the cam face 33f of the slide plate 33 and is connected to the brake mechanism of the take-up reel driving gear 13 via this plate, and the engaging portion 33g is connected to the brake mechanism of the take-up reel driving gear 13. Engages with the cancel plate to release the housing lock mechanism.

As shown in FIG. 6, the limit plate 34 has an elongated hole 34a for arranging a spring and an elongated hole 3 for a guide at the upper part of the figure.
4b, a guide elongated hole 34c is located at the lower part of the figure, and a locking hole 3 that is close to the upper edge of this elongated hole 34c and extends left and right in the figure.
4d, and also has a cam portion 34e that can come into contact with a guide pin of the tension arm 32, which will be described later, at the lower right portion of the figure. The cam portion 34e has two parallel cam surfaces 99a and 99b that are parallel to the direction of relative displacement between the limit plate 34 and the slide plate 33, and a continuous slope that slopes diagonally downward to the left in the figure. Cam surface 9
9b, and is located at a predetermined position of the slide plate 33 so as to be able to engage with the guide pin. This limit plate 34
The spring 38 described above is arranged in the elongated hole 34a,
Guide pins 39a and 39b installed on the slide plate 33 are slidably inserted into the elongated holes 34b and 34c, respectively, and the locking hole 33 of the slide plate 33 is inserted into the locking hole 34d.
The drive pin 37a of the drive lever 37 is slidably inserted through the drive lever 37c. The spring 38 has one end locked to the lower edge in the figure of the elongated hole 33d of the slide plate 33 and the other end to the upper edge of the elongated hole 34a of the limit plate 34 in the figure, and guides the slide plate 33 and the limit plate 34. The pins 39a, 39b are biased in the direction of contacting the upper edges of the elongated holes 34b, 34c. This limit plate 3
4 and the slide plate 33 are coupled by a spring 38 to enable relative displacement corresponding to the lengths of the elongated holes 34b and 34c.

Although not shown clearly in the figure, the limit plate 34 comes into contact with the arm supporting the impedance roller 21 mentioned above when the loading pole LP moves upward in the figure, and moves the impedance roller 21 out of the movement trajectory of the loading pole LP. Prevent interference.

The tension arm 32 has a base 32a and a base 32a.
The arm portion 32b is integrally extended from the base portion 32.
a is supported by the support bin 35 so as to be relatively rotatable, and the tension pole 23 is supported at the tip of the arm portion 32b.

The base portion 32a is formed with an arc-shaped adjustment hole 40a centered on the support bin 35, and the arm portion 32b is formed with a screw hole corresponding to the adjustment hole 40a.
2b is a screw 5 that passes through the adjustment hole 40a and is screwed into the screw hole.
0, the relative position in the rotational direction is fixed so as to be adjustable. Also,
Both ends of a brake band 41 are fixed to the base 32a on the left side in the figure, spaced apart vertically in the figure, and a locking part 40 is attached on the left side in the figure.
c is formed to lock the end of the tension spring 42. The brake band 41 is wrapped around the supply reel stand 12 and tightens the supply reel stand 12 by rotating the tension arm 32 counterclockwise in the figure, thereby braking the rotation of the supply reel stand 12. The tension spring 42 is
The tension arm 32 is stretched between the locking portion 40c of the base 32a and the locking portion 33e of the slide plate 33, and urges the tension arm 32 counterclockwise in the figure. The arm portion 32e has the aforementioned tension pole 23 erected at its tip, and a guide pin 43 erected in the middle. Guide pin 43
is slidably inserted into a guide groove 11b formed in the chassis 11. This guide groove 11b consists of a part 49a extending vertically in the figure and a part 49b extending substantially in the left-right direction in the figure, which are smoothly continuous, and this part 49b is a guide for the escape of the drive pin 37a, which will be described later. Groove 1
It is continuous with 1a. This guide groove 11b has a portion 49
b is defined as a portion that allows the tension arm 32 to swing, and portion 49a is defined as a portion that prohibits the tension arm 32 from swinging and restricts the posture of the tension arm 32.

The above-mentioned slide plate 33 and slide plate 34
, the guide pin 43 and the guide groove 11b constitute a braking prohibition mechanism 101, and the tension arm 32, brake band 41, tension pole 33 and tensicon spring 42 constitute a tension servo mechanism 103.

The drive lever 37 is provided on the back surface of the chassis 11, and its intermediate portion is rotatably supported by the chassis 11.

As described above, this drive lever 37 has a drive pin 37a provided at one end that is connected to the guide groove 11a of the chassis 11.
is inserted into the locking hole 33c of the slide plate 33 and the locking hole 34d of the limit plate 34, and a pin 37b is implanted at the other end, and the pin 37b connects to the cam gear 44.
It is inserted into the spiral cam hole 44a. Cam gear 44
has a disk shape and is rotatably supported by the chassis 11, and a gear 44b is formed on the outer periphery of the above-mentioned spiral cam hole 44a. The cam gear 44 is connected to a mode control motor via a gear train meshing with the gear 44b, and is driven by the mode control motor in conjunction with the aforementioned ball pace.

Although not clearly shown in the figure, the mode control motor is connected to the ball pace that supports the loading pole LP via various mechanisms.

In the magnetic tape recording and reproducing apparatus of this embodiment, a tension arm 32 having a tension pole 23 at its tip is swingably supported on a slide plate 33 driven by a mode control motor, and a tension arm 32 is swingably supported to eject a tape cassette.
EJECT), fast forward or rewind tape 16 (FF
/REW), -time stop (to RECLOC), play (PL
In response to the operation of operation buttons such as AY) and STOP, the loading motor is energized to drive the loading pole LP and simultaneously move the slide plate 33 to a position corresponding to the mode.

For example, when installing a cassette, the cam gear 44
is in the FF/REW mode position shown in FIG. The fulcrum, ie, the support bin 35, is also located near the bottom in the figure. At this time, the guide pin 43 of the tension arm 32 is positioned below the portion 49a of the guide groove 11b, so that its left and right movement is restricted, and thereby the movement of the tension pole 23 is also restricted. In this state, the slide plate 3
3, that is, the tension arm 32 is in a state where the brake band 41 is relaxed as it approaches the supply reel stand 12,
The supply reel stand 12 is not braked by the brake band 41 either. Although not shown, this tension pole 23 is located at a position corresponding to a notch in the lower front part of the cassette, and each loading pole LP is also located at a position corresponding to a notch of the cassette, and these balls 23. The LP can be loosely inserted into the notch at the bottom of the cassette when the cassette housing is lowered as the cassette is loaded.

Here, when the cassette is installed, the RECLO
As shown in the CK mode, the cam gear 44 is driven by a mode control motor (not shown) and rotates by a predetermined angle counterclockwise in the figure from the state shown in FIG. 2, and the slide plate 33 moves upward by a predetermined distance in the figure. Support bin 3
5 also moves upward in the figure, and the tension arm 3
2, the guide bin 43 slides within the portion 49a of the guide groove lie and moves to the portion 49b, resulting in the entire movement. At this time, in the limit plate 34, the parallel cam surface 99a of the cam portion 34e is located at the connecting portion with the guide groove 11a of the guide groove 11e, and the guide pin 43 is urged by the spring 42 to this parallel cam surface 99a. Because of this contact, movement of the guide pin 43 to the left in the figure is prevented, movement of the tension arm 32 is restricted, and the tension servo mechanism is held in a non-operating state. Note that the tension pole 32 is located at an inward position to weaken the tape tension, and the tension pole 32 is located at an inward position to weaken the tape tension.
The tension of No. 6 is set at a relaxed state to prevent tape damage.

Next, when the PLAY or REC operation button is operated (PLAY or RFC mode), the cam gear 44 further rotates by a predetermined angle counterclockwise in the figure, as shown in FIG. Then, only the limit plate 34 moves upward in the figure, and the limit plate 34 positions the parallel cam surface 99b of the cam portion 34e on the guide groove 11b and opens, so that the tension arm 32 also has the guide pin 43 in a free state. The tension servo mechanism that rotates counterclockwise due to the biasing force of the spring 42 and moves the tension pole 23 leftward in the figure to apply tension to the tape 16 is activated. That is, when the tension of the tape 16 is small and is relaxed, the tension arm 32 is rotated counterclockwise in the figure by the elastic force of the spring 42 and the band brake 41 is rotated.
increases the braking force on the supply reel stand 12, and
When the tension of the tape 16 is large, the brake bunt 41 is rotated clockwise in the figure to weaken the braking force applied to the supply reel stand 12, thereby causing the tape 16 to swing in accordance with the tension. The braking force of the supply reel stand 12 is controlled to adjust the tension of the running tape 16 to be constant.

As mentioned above, when the ball base shifts to the PLAY or RFC mode after reaching the loading completion position, the tension servo mechanism is activated, which prevents an increase in the drive load on the ball base and prevents the tape tension from becoming excessive. This can be prevented.

In addition, in this PLAY or REC mode,
The limit plate 34 extends the spring 38 and uses the biasing force upward in the figure generated against the slide plate 33 as a pressure force for positioning. This reliably prevents the slide plate 33 from moving due to external loads and the like, fixes it in the same position, that is, fixes the fulcrum of the tension arm 32, and provides a stable and reliable tension servo mechanism.

When the PAIISH operation button is operated here, the state shown in FIG. The cam portion 34e of the plate 34 presses the guide pin 43 to the right in the figure to hold the tension arm 32 in a state where the tension pole 23 moves in the direction (inward) to loosen the tension on the tape 16, as described above. It is the same as.

Furthermore, when the FF/REW operation button is operated, the state shown in FIG. and tape 1 in this state.
Fast forward or rewind 6. At this time, the tension pole 23 does not come into contact with the tape 16 running at high speed.

Furthermore, when the 5TOP operation button is operated instead of the FF/REW operation button, the state shown in FIG. ing.

Then, when the EJECT operation button is operated, the first
As shown in the figure, the cam gear 44 rotates a predetermined angle counterclockwise in the figure from the state shown in FIG.
The slide plate 33 is also located further down in the figure, and unlocks and raises the cassette housing (not shown) to eject the cassette.

In the above-mentioned embodiment, the tension arm 32 is controlled entirely by moving the slide plate 33, but for example, the tension pole 2
The tension arm 32 is only moved from the unloading position located in the notch of the cassette No. 3 to the loading position where the tension servo mechanism is actuated by a support member such as the slide plate or link member described above.
The fulcrum may be moved and other movements may be controlled by other mechanisms.

Further, although the above-described embodiment exemplifies a VTR, it goes without saying that the present invention can also be applied to a digital audio recorder (R-DAT).

(Effects of the Invention) As explained above, according to the magnetic tape recording and reproducing apparatus according to the present invention, the brake mechanism of the supply reel stand is released until the loading pole reaches the loading position, so that the loading load is reduced. It is possible to prevent the tape tension from becoming excessive, and it is also possible to prevent the tape tension from becoming excessive during loading.

[Brief explanation of drawings]

1 to 8 show a tape running mechanism of a magnetic tape recording/reproducing apparatus according to an embodiment of the present invention, and FIGS. 1, 2, 3, and 4 show main parts in different states. A plan view, Fig. 5 is a perspective view of the main parts, Fig. 6 is a plan view of the main parts of -, Fig. 7 is a plan view of other main parts of -, and Fig. 8 is a schematic diagram of the tape running system. be. 11... Main chassis, 12... Supply reel stand,
13... Take-up reel driving gear, 14... Supply reel, 15... Take-up reel, 16... Magnetic tape, 2
3... Tension pole, 32... Tension arm, 33... Slide plate, 34... Limit plate, 35... Support pin, 42... Tension spring, 101... Braking prohibition mechanism, 103...
Tension servo mechanism. Patent Applicant Victor Japan Co., Ltd. No. 3 Figure 5 1A Figure 8

Claims (1)

[Claims] A magnetic head is provided that moves along a predetermined trajectory to pull out a magnetic tape suspended between a supply reel and a take-up reel in a cassette, and rotates the magnetic tape at a predetermined position on the trajectory. A loading pole is wound around the drum over a predetermined angle range, and a tension pole installed at the tip of a swingably supported tension arm is biased by a tension spring and comes into contact with the magnetic tape, and a brake band is connected to the tension arm. is wound around the supply reel base,
a tension servo mechanism that adjusts the tension of the magnetic tape by tightening the supply reel stand in response to the swinging of the tension arm and applying braking force to the supply reel stand; and a tension servo mechanism that adjusts the tension of the magnetic tape; 1. A magnetic tape recording and reproducing apparatus comprising: a braking inhibiting mechanism that inhibits braking of the supply reel stand by the tension servo mechanism until the tension servo mechanism reaches the tension servo mechanism.