JP2501781Y2 - Tape guide mechanism - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape guide mechanism, and more particularly to a tape guide mechanism that guides a tape that has passed through a capstan.

2. Description of the Related Art A magnetic recording / reproducing apparatus such as a digital audio tape recorder is provided with a tape guide mechanism for guiding the tape running. As a conventional tape guide mechanism, for example, the Japanese Patent Application No. Sho 63
-There is 169460. In this mechanism, the gear that meshes with the drive gear drives the tape loading member to the tape loading position, and the tape loading member rotates the pinch roller arm of the pinch roller crimping mechanism to move the pinch roller to the capstan side. Has become. In addition, the pinch roller is a spring stretched between the pivot arm and the pinch roller arm when the pivot arm provided coaxially with the pinch roller arm abuts against a part of the gear and pivots. Is pulled, and the pulling force pushes it against the capstan.

However, in the above-mentioned conventional mechanism, since the pinch roller arm is rotated through the gear that meshes with the drive gear, the position of the pinch roller supported at the tip of the pinch roller arm is changed by the backlash of the gear. There may be variations, the pressing force of the pinch roller on the capstan fluctuates,
Alternatively, there is a problem that the stop position may vary when the pinch roller arm rotates to the standby position (unloading position) separated from the capstan in the unloading mode. Further, in the above-mentioned conventional mechanism, a capstan pressing spring must be provided between the pinch roller arm and the rotating arm, and a return spring for urging the pinch roller arm in the return direction must be provided. There is a problem that the number of parts is large and the configuration is complicated.

In view of this, the present invention provides a tape guide mechanism that solves the above-mentioned problems by switching the biasing direction of the pinch roller arm according to its rotational position by a biasing member between the pinch roller arm and the guide post support arm. The purpose is to provide.

Means for Solving the Problems A tape guide mechanism of the present invention presses a tape against a cam plate that is driven when switching between a tape loading mode and a tape unloading mode, and a capstan that rotates during recording and reproduction,
A pinch roller for running the tape in the winding direction; a pinch roller arm for supporting the pinch roller having a contacting pin protruding downward and having a biasing member locking portion for locking the biasing member at one end; A guide post that guides the tape fed from the capstan, an engagement pin that is located between the cam plate and the pinch roller arm, and that engages with the guide post and a cam groove of the cam plate, A protrusion that contacts the contact pin; and a biasing member latching portion that latches the biasing member. The biasing member latching portion is in slidable contact with the cam portion of the cam plate. A guide post support arm for displacing the guide post to a standby position separated from the tape, one end of which is hooked by a biasing member hooking portion of the pinch roller arm, and the other end of which is The guide post supporting arm is urged by the urging member engaging portion of the guide post supporting arm and urges the pinch roller arm so that the pinch roller presses the capstan in the recording / reproducing mode, and the guide post supporting arm in the tape unloading mode. To a standby position, and for urging the pinch roller arm so that the pinch roller is held at a standby position separated from the capstan by the guide post support arm.

Action One urging member urges the pinch roller to rotate in the direction in which the pinch roller contacts the capstan with the rotation of the guide post support arm in the tape loading mode, and guides in the tape unloading mode. The post support arm is biased to and held at the standby position, and the pinch roller arm is held at the standby position to eliminate variations in the pivot position of the pinch roller arm and reduce the number of parts.

Embodiment FIG. 1 shows an embodiment of the tape guide mechanism according to the present invention. FIG. 1 shows a tape unloading mode, that is, a tape cassette eject state.

In the figure, a cam plate 1 is provided so as to slide in the X ₁ and X ₂ directions according to each mode, and a cam gear 2 that rotates by receiving a rotational driving force from a motor (not shown). It is connected to a turning lever 3 that turns according to a turning angle. Therefore, the cam plate 1 is slid to the position corresponding to each mode by the rotating position of the cam gear 2. A control circuit (not shown) obtains the position of the cam plate 1 based on a signal from a detection member that detects the rotational position of the cam gear 2.

4 is a tape loading member on the supply side, 5 is a tape loading member on the winding side, 6 is a pinch roller,
Reference numeral 7 is a supply side link mechanism for driving the tape loading member 4, 8 is a link mechanism for driving the tape loading member 5, and 9 is a tape guide mechanism. Cam plate 1
Is the first with which the engagement pin 7a of the link mechanism 7 on the supply side is engaged.
Cam hole 1c, the second cam hole 1d with which the engaging pin 8a of the winding side link mechanism 8 engages, and the engaging pin 9a of the tape guide mechanism 9 engage with each other to form an L shape. It has a third cam hole 1e.

The tape loading mechanism 10 having the above structure is provided so as to be movable up and down together with the cam plate 1, and the tape cassette mounting tape loading members 4 and 5 and the pinch roller 6 are elevated to the upper surface of the main chassis (not shown).

Reference numeral 11 denotes a capstan that rotates at a predetermined rotation speed during recording / reproduction, and is guided by the tape loading members 4 and 5 and passes through a rotating drum (not shown) to run the tape in the winding direction.

The tape guide mechanism 9 has a pinch roller arm 12 that supports a pinch roller, and a guide post support arm 14 that supports a guide post 13 that guides the tape traveling position. The pinch roller arm 12 is located above the cam plate 1 and supported by the shaft 15, and rotatably supports the pinch roller 6 on the upper surface of the tip portion 12a. Further, the pinch roller arm 12 has a spring hooking portion 12b projecting to the other end side, and a support portion 12c for supporting the contact pin 16 projecting downward is provided between the tip portion 12a and the hooking portion 12b. Have.

The guide post support arm 14 is the pinch roller arm described above.
The pinch roller arm 12 is rotatably supported by a shaft 17 which is located between the cam plate 1 and the cam plate 1 and which penetrates an arc-shaped hole 12d of the pinch roller arm 12. Guide post support arm
Reference numeral 14 denotes a support portion 14a that supports the guide post 13 and a support portion 14b that supports the engagement pin 9a that fits in the lower cam groove 1e.
And a protruding portion 14c that protrudes so as to contact the contact pin 16.
And a spring retaining portion 14d extending in the opposite direction to the support portion 14a.

18 is a coil spring (biasing member), one end of which is hooked on the spring hooking portion 12b of the pinch roller arm 12, and the other end of which is hooked on the spring hooking portion 14d of the guide post support arm 14.
The pinch roller arm 12 and the guide post support arm 14 are biased in opposite directions. The coil spring 18 urges the pinch roller arm 12 in the clockwise direction so that the pinch roller 6 presses the capstan 11 in the tape loading mode, as will be described later, and in the tape unloading mode, as shown in FIG. The support arm 14 is urged counterclockwise to hold it in the standby position.

Therefore, in the tape guide mechanism 9, the pins 15, 17 of the pinch roller arm 12 and the guide post support arm 14,
The positional relationship between the contact pin 16 and the spring retaining portions 12b and 14b is set as shown in FIG. That is, in FIG. 2, in the present embodiment, the shaft 17 is separated from the spring retaining portion 14d by a distance L ₁ (= 10.06).
mm), the distance L ₂ (= 8.26 mm) from the shaft 17 to the position where the contact pin 16 contacts the protrusion 14c, and the distance l ₁ (from the shaft 15 to the position where the contact pin 16 contacts the protrusion 14c). = 15.02mm), axis 15
The distance l ₂ (= 15.18 mm) between the spring retaining portion 12b and the spring retaining portion 12b is determined. Also, in the unloading mode, the angle α ₂ (= 65.8) with the shafts 15 and 17 with respect to the acting direction of the spring force F ₁ of the spring 18
3 °), θ ₁ (= 100.36 °), and the angle F ₂ (= 79.86) between the shaft 17 and the force F ₂ acting on the protrusion 14c that abuts the abutment pin 16.
The angle α ₁ (= 2.82 °) between the force f and F ₂ is determined. Note that F ₂ is the force that the guide post support arm 14 receives from the pinch roller arm 12.

Here, when the moment around the axis 17 in the tape unloading mode is calculated, in the B direction (clockwise direction), M _B = F ₂ L ₂ sin θ ₂ ...

[F ₂ = f · 1 / cos α ₁ fl ₁ = F ₁ l ₂ sin α ₂ ,] For the A direction (counterclockwise direction), M _A = F ₁ L ₁ sin θ ₁ ...

When the above numerical values are applied to the above equation, M _A = 9.9F ₁ M _B = 7.5F ₁ and M _A > M _B. Therefore, the guide post support arm 14 rotates in the A direction (counterclockwise direction) in the tape unloading mode.

Therefore, in the tape unloading mode, the guide post supporting arm 14 is biased counterclockwise by the pulling force of the spring 18 and is held at the standby position shown in FIG. The pinch roller arm 12 is urged to rotate in the clockwise direction by the pulling force F ₁ of the spring 18, but the projection 14c of the guide post support arm 14 causes the contact pin 16 to move due to the positional relationship shown in FIG. The spring 18 is pressed in a counterclockwise direction with a force larger than the tensile force of the spring 18. Therefore, the pinch roller arm 12 is urged to rotate counterclockwise via the guide post support arm 14 and held at the standby position shown in FIG.

Next, the operation of the tape guide mechanism 9 having the above structure will be described.

When a tape cassette (not shown) is loaded in the tape unloading mode shown in FIG. 1 and a recording / reproducing mode operation is performed, the cam gear 2 is driven counterclockwise. As a result, the rotation lever 3 having the pin 3a that engages with the cam groove 2a of the cam gear 2 rotates counterclockwise about the shaft 3b as a fulcrum. At the same time, the cam plate 1 which is connected to the pin 3c of the rotating lever 3 and has the long holes 1f and 1g extending in the X ₁ and X ₂ directions is guided by the pins 19 and 20 fitted into the long holes 1f and 1g. Slide in the X ₂ direction.

Since the engagement pins 7a and 8a of the link mechanisms 7 and 8 are fitted in the cam holes 1c and 1d of the cam plate 1, the cam plate 1 is displaced in the X ₂ direction and extends as shown in FIG. . Therefore, the tape loading members 4 and 5 have a link mechanism.
The movement of 7, 8 moves to the tape loading position along the guide grooves 21, 22 on the chassis. As a result, the tape (not shown) in the tape cassette is pulled out and wound around the outer circumference of the rotary drum (not shown).

During the above tape loading operation, the cam plate 1 is X ₂
Slides in the direction, and the cam hole of the cam plate 1
Since the engagement pin 9a fitted to 1e is pressed in the same direction, the guide post support arm 14 having the engagement pin 9a rotates clockwise about the shaft 17 as shown in FIG. As a result, the guide post 13 moves clockwise from the standby position to move the tape 23 (in FIG. 3, in the tape cassette (not shown)).
(Indicated by the one-dot chain line) to the tape running position.

Further, as the guide post support arm 14 rotates clockwise as described above, the protrusion 14 is generated by the tensile force of the spring 18.
The contact pin 16 in contact with c moves. Therefore, the pinch roller arm 12 rotates clockwise about the shaft 15 as a fulcrum. Therefore, the pinch roller 6 moves from the standby position (shown in FIG. 1) to a position close to the capstan 11 and pulls out the tape 23 in the tape cassette to the position shown in FIG.

Although FIG. 3 shows the tape loading state, the pinch roller arm 12 is in a stop mode in which the contact pin 16 contacts the protrusion 14c and cannot rotate any further, and the pinch roller 6 does not press the capstan 11. It shows the fast-forward and rewind modes.

In the recording / reproducing mode, the cam plate 1 is further driven in the X ₂ direction to be in the state shown in FIG. That is, when the cam plate 1 slides in the X ₂ direction and the engagement pin 9a reaches the end of the cam hole 1e, the guide post support arm 14 rotates further clockwise than the position shown in FIG. As a result, the protrusion 14c of the guide post support arm 14 is moved to the pinch roller arm 1
The pulling force of the spring 18 increases with the distance from the second contact pin 16. Therefore, the pinch roller arm 12 is displaced from the position shown in FIG. 3 to the position for pressing the capstan 11 as shown in FIG. At this time, the guide post support arm
The protrusion 14c of 14 is located apart from the contact pin 16 of the pinch roller arm 12, and the pinch roller 6 presses the tape 23 onto the capstan 11 by the pressing force of the spring 18. Therefore, the pinch roller 6 presses the tape 23 onto the capstan 11 with a constant pressing force without variation.

Therefore, the tape 23, which has been guided by the tape loading members 4 and 5 and has passed through the rotary drum (not shown), is sandwiched by the pinch roller 6 and the capstan 11 and is stable in the C direction (tape winding direction). After traveling, the tape passes through the guide post 13 and is wound up on a winding reel (not shown) in the tape cassette.

Thus, the spring 18 stretched between the pinch roller arm 12 and the guide post support arm 14 moves the pinch roller arm 12 via the guide post support arm 14 and the guide post support arm 14 in the tape unloading mode. The pinch roller 6 is provided so as to be held in the standby position and to urge the pinch roller arm 12 to rotate so that the pinch roller 6 presses the capstan 11 in the tape loading mode. Therefore, it is not necessary to separately provide the pinch roller arm 12 and the guide post support arm 14 with springs for urging them separately. That is, since the tape guide mechanism 9 can urge both members in accordance with the tape loading mode and the tape unloading mode by the single spring 18, the number of parts can be reduced and the structure can be simplified. ing.

In the eject mode, the cam plate 1 is driven in the X ₁ direction to perform the reverse operation of the tape loading operation, returning to the state shown in FIG.

Further, although the digital audio tape recorder has been described as an example in the above embodiment, the present invention is not limited to this, and a magnetic recording / reproducing apparatus other than this, for example, a video tape recorder, 8
Of course, it can be applied to a millimeter video tape recorder or the like.

Effect of the Invention As described above, in the tape guide mechanism according to the present invention, the pinch roller is pressed by the capstan in the tape loading mode by the biasing member stretched between the pinch roller arm and the guide post supporting arm, and the tape unwinding is performed. In the loading mode, the guide post can be held at the standby position and the pinch roller can be held at the standby position. Therefore, it is not necessary to separately provide a biasing member to both members, the number of parts can be reduced accordingly, and the structure can be simplified. Furthermore, the rotation of the pinch roller due to the backlash of the gear as in the conventional case can be achieved. It has the features that there is no position variation and the tape can be pressed against the capstan with a constant pressing force during recording and playback to stabilize the tape running.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a tape guide mechanism in a tape unloading mode, and FIG. 2 is a principle view for explaining a moment acting around an axis of a guide post supporting arm in a tape unloading mode. FIG. 3 is a plan view showing the stop mode, fast-forward and rewind mode after tape loading, and FIG. 4 is a plan view showing the recording / reproducing mode state. 1 ... Cam plate, 4,5 ... Tape loading member, 6 ... Pinch roller, 7,8 ... Link mechanism, 9 ...
Tape guide mechanism, 11 …… capstan, 12 …… pinch roller arm, 13 …… guide post, 14 …… guide post support arm, 16 …… contact pin, 18 …… coil spring.

Claims (1)

(57) [Scope of utility model registration request] 1. A cam plate that is driven when switching between a tape loading mode and a tape unloading mode, and a pinch roller that presses the tape against a capstan that rotates during recording and reproduction and that runs the tape in the winding direction. A pinch roller arm that supports a pinch roller having a contact pin that projects downward, and a guide that guides the tape fed from the capstan. A post, an engaging pin that is located between the cam plate and the pinch roller arm, and that engages with the guide groove, the cam groove of the cam plate, and a protrusion that abuts on the abutting pin;
A standby position in which the guide post is separated from the tape in the tape unloading mode by driving the cam plate by slidingly contacting the cam portion of the cam plate. And a guide post supporting arm to be displaced to one end, and one end of the guide post supporting arm is locked to the biasing member locking part of the pinch roller arm, and the other end is locked to the biasing member locking part of the guide post supporting arm. The pinch roller arm is urged so that the pinch roller presses against the capstan at the time, and the guide post supporting arm is urged to the standby position in the tape unloading mode, and the pinch roller via the guide post supporting arm. And a biasing member that biases the pinch roller arm so that the pinch roller arm is held at a standby position separated from the capstan, Tape guide mechanism.