GB2208744A - Tape recorder - Google Patents

Abstract

A tape recorder comprises a pinch roller 12 (112) Fig 10) mounted at a fixed location of a head mounting plate 10 , a capstan shaft 2 mounted for rotation on a stationary base plate 1 on which the head mounting plate 10 is mounted for reciprocal linear movement, a spring 15 normally biasing head mounting plate 10 to move pinch roller 12 into contact with capstan shaft 2, the position of magnetic head 11 for a reproduction mode being defined by the capstan shaft 2 against which pinch roller 12 on the head mounting plate 10 is pressed by the biasing force of spring 15. Stopping operating member (16) (Figs 1, 2, 8) used for cassette ejection also pushes head mounting plate 10 via lug 10c to its rest position against the bias of spring 15. The cassette is aligned on loading by conical portion (6a) of guide member (6) (Fig 6) of the capstan shaft fitting into one of the holes (8a) (Fig 7) of the cassette. The pinch roller construction/mounting is detailed w.r.t (Fig 5), an alternative being as (Fig 10). <IMAGE>

Description

TAPE RECORDER BACKGROUND OF THE INVENTION 1) Field of the Invention This invention relates to a tape recorder, and more particularly to improvements in or relating to a structure of a tape recorder for mounting a pinch roller for rotation on a head mounting plate on which a magnetic head is mounted.

2) D#escr#iption of the Prior Art A tape recorder is already known which includes a stationary base plate, a head mounting plate mounted for reciprocal movement on the base plate, a magnetic head mounted on the head mounting plate, a capstan shaft mounted for rotation on the base plate, a pinch roller movable into or out of contact with the capstan shaft in response to movement of the head mounting plate, and a spring for normally biasing the head mounting plate in a direction to move the pinch roller into contact with the capstan shaft.

In such a conventional tape recorder, a pivotal lever is mounted at an end thereof for pivotal motion on a base plate and has a pinch roller mounted for rotation at the other end thereof. The pivotal arm is normally biased by a spring in a direction to engage the pinch roller thereon with a capstan shaft. Thus, as a head mounting plate is moved, the pivotal arm is allowed to be pivoted by the biasing force of the spring until the pinch roller is contacted with the capstan shaft.

Meanwhile, the position of a magnetic head for a reproduction mode is defined by a spring for biasing the head mounting plate, on which the magnetic head is mounted, in a forward direction and a stopper located on the base plate.

Accordingly, such a conventional tape recorder as described just above requires a relatively large number of components including a pivotal arm, a spring for biasing the pivotal arm, and a stopper for defining the limit position of a head mounting plate in a forward direction, which requires a corresponding cost.

Further, since the head mounting plate is biased in the forward direction by the biasing force of the spring, the head mounting plate will be moved back rapidly to its home position when an arresting mechanism for arresting the head mounting plate at its forwardly moved position against the biasing force of the spring is released by a cassette holder. Consequently, at the home position of the head mounting plate, that is, at the end of the returning movement of the head mounting plate, the head mounting plate is brought into collision with the stopper on the base plate. Accordingly, there is a problem that a fastening screw for the magnetic head may get loose by impact upon such collision.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tape recorder wherein a structure for mounting a pinch roller on a head mounting plate is simplified and can be produced at a reduced cost and a fastening screw for a magnetic head may not readily get loose.

In order to attain the object, according to the present invention, there is provided a tape recorder, comprising a stationary base plate, a head mounting plate mounted for reciprocal movement on the base plate, a magnetic head mounted on the head mounting plate, a capstan shaft mounted for rotation on the base plate, a pinch roller movable into or out of contact with the capstan shaft in response to movement of the head mounting plate, and a spring for normally biasing the head mounting plate in a direction to move the pinch roller into contact with the capstan shaft, wherein the pinch roller is mounted at a fixed location of the head mounting plate and the position, of the magnetic head for a reproduction mode of the tape recorder is defined by the capstan shaft against which the pinch roller on the head mounting plate is pressed by the biasing force of the spring.

With the tape recorder, the position of the magnetic head for the reproduction mode is defined by the pinch roller pressed against the capstan shaft by the biasing force of the spring which biases the head mounting plate in the direction.

Accordingly, the tape recorder of the present invention eliminates such components of a conventional tape recorder as a pivotal arm, a spring for biasing the pivotal arm and a stopper for defining the limit position of the head mounting plate in the forward direction. Accordingly, an effect can be anticipated that the structure for mounting the pinch roller on the head mounting plate is simplified and can be produced at a reduced cost. Another effect can also be anticipated that the effect of the pinch roller as a damper will prevent a fastening screw for the magnetic head from getting loose by impact.

A specific embodiment of the present invention will now be described in detail by way of-example with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a mechanism of a tape recorder according to the present invention; FIG. 2 is a bottom plan view of the tape recorder mechanism of FIG. 1; FIG. 3 is a front elevational view of the tape recorder mechanism of FIG. 1 as viewed in a direction of an arrow mark III of FIG. 1; FIG. 4 is a perspective view of a head mounting plate; FIG. 5 is a cross sectional view of a pinch roller; FIG. 6 is a perspective view, partly broken, illustrating operation of the head mounting plate of FIG. 4; FIG. 7 is a top plan view, partly broken, showing a magnetic head and the pinch roller contacted with a tape within a tape cassette; FIG. 8 is a top plan view similar to FIG. 1 but showing the tape recorder mechanism in a reproducing condition;; FIG. 9 is a bottom plan view of the tape recorder mechanism of FIG. 1 in the reproducing condition; and FIG. 10 is a cross sectional view of a modified form of pinch roller which may be employed in a tape recorder of the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Referring first to FIGS. 1 to 3, there is shown a mechanism of a tape recorder according to the present invention. The tape recorder mechanism shown includes a capstan shaft 2, a reel shaft 3, a motor 4 for driving the capstan shaft 2 and the reel shaft 3 to rotate, and a switch 5 for interrupting energization of the motor 4, all located on a chassis or base plate 1.

Referring also to FIG. 6, the capstan shaft 2 is fitted from the lower face side of the chassis 1 into and supported for relative rotation on a hub member 6 secured to a predetermined location of the chassis 1 and extends upwardly above an upper face of the chassis 1.

A snap ring 7 such as an E-snap ring is sna into an annular groove 2a formed around an outer periphery of the capstan shaft 2 and is located for engagenlent with an upper end face of the hub member 6 to prevent the capstan shaft 2 from being inadvertently pulled downwardly off the hub member 6.

The hub member 6 has a guide portion 6a of a truncated right circular conical shape adjacent an upper end thereof. Thus, when a tape cassette 8 is moved to a loaded position as shown in FIG. 7, the guide portion 6a of the hub member 6 is fitted into one of a pair of capstan shaft fitting holes 8a formed in the tape cassette 8, and thereupon it provides an automatic aligning action to the tape cassette 8. Consequently, a guide pin which is conventionally provided specially for providing an automatic aligning action can be eliminated.

Referring back to FIGS. 1 to 3, the motor 4 is electrically connected to a suitable power source not shown via the switch 5. Turning power of the motor 4 is transmitted to the capstan shaft 2 by way of a power transmitting mechanism 9.

Referring to FIG. 2, the power transmitting mechanism 9 includes a first pulley 9a securely mounted on an output power shaft 4a of the motor 4, a second pulley 9b of a greater diameter securely mounted at a lower end of the capstan shaft 2, and an endless belt 9c made of a rubber material or the like and extending between and around the first and second pulleys 9a, 9b.

Referring to FIGS. 2, 4 to 6, a head mounting plate 10 is mounted for movement within a predetermined range on the lower face of the chassis 1. The head mounting plate 10 has a main plate portion 10a having a substantially triangular or trapezoidal shape in plan with a wide side located at one longitudinal end and a narrow side located at the other longitudinal end thereof, a side wall lOb extending perpendicularly upwardly from the wide side of the main plate portion 10a, and a bent engaging lug lOc extending perpendicularly upwardly from a corner of the narrow side of the main plate portion 10a and having an arcuate shape in plan.The main plate portion 10a of the head mounting plate 10 has an elongated hole 10d formed at a portion near the narrow side thereof, and a vertically downwardly bent lug Ib formed on the chassis 1 extends through the elongated hole 10d of the head mounting plate 10. Meanwhile, the side wall lOb of the head mounting plate 10 has a pair of engaging holes or slits not shown formed at locations adjacent opposite ends thereof, and a pair of guide tabs lc formed on the chassis 1 extend through the engaging holes of the side wall lOb of the head mounting plate 10. Thus, the head mounting plate 10 is guided for movement in leftward and rightward directions in FIG. 2.

A reproducing magnetic head 11 and a pinch roller 12 are mounted on an upper face adjacent the wide side of the head mounting plate 10.

The magnetic head 11 is designed such that a front face thereof is contacted with a tape 8b within a tape cassette 8 as seen in FIG. 7.

The pinch roller 12 is mounted for contact with the capstan shaft 2 with a tape 8b of a tape cassette 8 interposed therebetween as shown in FIG. 7. As particularly shown in FIG. 5, the pinch roller 12 is supported for rotation on and between a pair of upper and lower mounting walls 14a, 14b of a mounting bracket 14 made of an elastic synthetic resin material and secured at a location of the upper face of the main plate portion 10a of the head mounting plate 10 sidewardly of the magnetic head 11 by means of a screw 13.

The pinch roller 12 includes a roller body 12a made of a rubber material, and a shaft 12b made of a synthetic resin material and fitted for integral rotation at the center of the roller body 12a. In assembling the pinch roller 12, upper and lower opposite end portions of the shaft 12b thereof are forced laterally into fitting recesses 14c of a substantially C-shape in plan formed at central portions of ends of the upper and lower mounting walls 14a, 14b of the mounting bracket 14 making use of the elasticity of the mounting bracket 14. In this manner, the pinch roller 12 is assembled readily in position on and between the upper and lower mounting walls 14a, 14b of the mounting bracket 14 by a single operation, and in the assembled state, the pinch roller 12 can be rotated freely but cannot readily come off the mounting bracket 14.

Accordingly, the shaft 12a of the pinch roller 12 cannot be moved laterally relative to the head mounting plate 10.

The head mounting plate 10 is normally biased toward its operation mode position, that is, in the leftward direction in FIG. 2 by a coil spring 15. The coil spring 15 is secured at an end thereof to the main plate portion 10a of the head mounting plate 10 and at the other end thereof to the chassis 1.

Thus, the pinch roller 12 is pressed against the capstan shaft 2 by the biasing force of the coil spring 15 thereby to define a reproduction mode position of the magnetic head 11.

The head mounting plate 10 is pushed to move in the rightward direction in FIG. 2 toward its rest position against the biasing force of the coil spring 15 when a stopping operating member 16 which is also used for ejecting operation is moved from its operation mode position to its rest position, Referring to FIG. 2, the stopping operating member 16 has a main body portion 16a, a side wall portion 16b extending vertically upwardly from a side edge of the main body portion 16a, and a front wall portion 16c extending perpendicularly outwardly from a forward end of the side wall portion 16b. The stopping operating member 16 is mounted for movement within a predetermined range with the main body portion 16a thereof located on the lower face of the chassis 1 and with the side wall portion 16b thereof located on an outer face of a side wall la (FIG. 1) of the chassis 1.

The main body portion 16a of the stopping operating member 16 has a guide face 16d in the form of an inclined curved face formed on the other edge thereof for sliding contact with the bent engaging lug 10c of the head mounting plate 10. Thus, if the stopping operating member 16 is manually pushed to move from its operation mode position to its first actuated position or fast feeding mode position, the head mounting plate 10 is moved, through sliding engagement between the guide face 16d of the stopping operating member 16 and the bent engaging lug lOc of the head mounting plate 10, from its reproduction mode position against the biasing force of the coil spring 15 to its fast feeding mode position in which the pinch roller 12 is spaced by a little distance from the capstan shaft 2. If the stopping operating member 16 is further pushed to move from the first actuated position to a second actuated position or ejection/rest position, the head mounting plate 10 is further moved, through sliding contact between the guide face 16d and the bent engaging lug lOc, against the biasing force of the coil spring 15 to a rest position or ejecting position in which the pinch roller 15 is spaced by a maximum distance from the capstan shaft 2. The stopping operating member 16 is normally biased toward the reproduction mode position in an upward direction in FIG. 2 by a coil spring 17. The coil spring 17 is secured at one end thereof to the lower face of the chassis 1 and at the other end thereof to a lower face of the main body portion 16a of the stopping operating member 16.

By moving the stopping operating member 16 to its ejecting position, a cassette holder 18 is pivoted from a set position to a reset position. To the contrary, by putting a tape cassette 8 into the cassette holder 18 and pushing the tape cassette 8 in to a predetermined position, the cassette holder 18 is pivoted from the reset position to the set position.

The cassette holder 18 is mounted for pivotal motion on the upper face of the chassis 1-.

Referring to FIG. 7, as the cassette holder 18 is pivoted from the reset position to the set position, one of the capstan shaft fitting holes 8a and one of a pair of reel shaft fitting holes 8c of the tape cassette 8 inserted in the cassette holder 18 are fitted on the capstan shaft 2 and the reel shaft 3, respectively, while the magnetic head 11 and the pinch roller 12 are moved into the tape cassette 8 through openings 8d, 8e, respectively, formed in the tape cassette 8 until they are contacted with a tape 8b within the tape cassette 8.

In order to allow the magnetic head 11 and the pinch roller 12 to move into and out of the tape cassette 8, a side wall 18a of the cassette holder 18 is divided into three sections as shown in FIG. 1 which define therebetween a pair of openings opposing to the openings 8d, 8e of the tape cassette 8.

Then, as the cassette holder 18 is pivoted from the set position to the reset position, the capstan shaft 2 and the reel shaft 3 are removed from the capstan shaft fitting hole 8a and the reel shaft fitting hole 8c of the tape cassette 8, respectively, while the magnetic head 11 and the pinch roller 12 are also removed from within the tape cassette 8 and from the tape 8b.

The cassette holder 18 is operatively connected to the stopping operating member 16 such that when the stopping operating member 16 is moved forwardly from the reproduction mode position to the ejecting position, the cassette holder 18 is pivoted away from the chassis 1 to the reset position. After pivotal motion of the cassette holder 18 to the reset position, the stopping operating member 16 is arrested at its ejecting position against the biasing force of the coil spring 17. To the contrary, when the stopping operating member 16 is moved reversely from the ejecting position to the reproduction mode position, the cassette holder 18 is pivoted toward the chassis 1 to its set position.

Now, operation of the tape recorder according to the present invention having such a construction as described above will be described. In FIGS. 1 to 3, the tape recorder is shown in its rest condition. In this condition, the cassette holder 18 is in its reset position, the stopping operating member 16 is in its rest position, and the head mounting plate 10 is held, due to engagement of the guide face 10c thereof with the guide face 16d of the stopping operating member 16, at its rest position in which the pinch roller 12 thereon is spaced farthest away from the capstan shaft 2 against the biasing force of the coil spring 15 and the switch 5 is held at an off or motor deenergizing position.

In this condition, if a tape cassette 8 is inserted into the cassette holder 18 and then further pushed in strongly, the cassette holder 18 is pivoted to the set position in which the capstan shaft 2 and the reel shaft 3 are fitted into corresponding ones of the capstan shaft fitting holes 8a and the reel shaft fitting holes 8c of the tape cassette 8, respectively, as shown in FIGS. 7 and 8. Meanwhile, as the cassette holder 18 is pivoted to the set position, the stopping operating member 16 is moved to the operation mode position by the biasing force of the coil spring 17.

Upon such movement of the stopping operating member 16, the switch 5 is brought to a motor energizing position so that the motor 4 is energized to rotate in the clockwise direction in FIG. 2.

Further, as the stopping operating member 16 is moved to its operative mode position, the head mounting plate 10 is released from its arrested condition at the rest position by the stopping operating member 16 so that it is moved in the leftward direction in FIG. 2 by the biasing force of the coil spring 15 to its operative mode position, that is, to its reproduction mode position as shown in solid lines in FIG. 6 in which the magnetic head 11 contacts with a tape 8b within the tape cassette 8 and the pinch roller 12 is pressed against the capstan shaft 2 via the tape 8b as seen in FIG. 7.

Since the turning power of the motor 4 is transmitted to the capstan shaft 2 via the power transmitting mechanism 9, the capstan shaft 2 is rotated in the clockwise direction in FIG. 2. The turning power of the motor 4 is also transmitted to rotate the reel shaft 3 in the clockwise direction in FIG. 2. Accordingly, the tape 8b of the tape cassette 8 is fed in a direction indicated by an arrow mark in FIG. 7 in order to effect operation for the reproduction mode in such a condition of the tape recorder as shown in FIGS. 8 and 9.

Operation of the reproduction mode is effected in this manner. Then, if the tape 8b is completely wound up from one of a pair of reels not shown within the tape cassette 8 which is not fitted on the reel shaft 3 to the other reel fitted on the reel shaft 3, the switch 5 is turned off to stop energization of the motor 4.

Consequently, the motor 4 is stopped to stop rotation of the capstan shaft 2.

In this condition, if the stopping operating member 16 is pushed in in the downward direction in FIG. 9 to its rest position against the biasing force of the coil spring 17 in order to remove the tape cassette 8 from the cassette holder 18, the engaging lug 10c of the head mounting plate 10 is pressed by the guide face 16d of the stopping operating member 16 so that the head mounting plate 10 is moved in the rightward direction in FIG. 8 against the biasing force of the coil spring 15 until the pinch roller 12 comes to its rest position in which it is spaced farthest away from the capstan shaft 2 and the pinch roller 12 and the magnetic head 11 are spaced away from the tape cassette 8.Meanwhile, as the stopping operating member 16 is moved to its rest position, it is thereafter arrested at the rest position at which it causes the switch 5 to assume the motor deenergizing position while the cassette holder 18 is pivoted to its reset position. Upon such pivotal motion of the cassette holder 18, the tape cassette 8 is pushed outwardly of the cassette holder 18 and the cassette holder 18 is arrested at its reset position.

While the preferred form of the present invention has been described, it is to be understood that various modifications and variations of the present invention are possible in the light of the above teachings. For example, while in the embodiment described above the pinch roller 12 is constituted such that the shaft 12b is fitted for integral rotation at the center of the roller body 12a and supported for rotation on the mounting bracket 14, such a modified pinch roller 112 as shown in FIG. 10 may otherwise be employed wherein a roller body 112a is fitted for rotation on a shaft 112b secured to a bracket 114.

Claims (3)

CLAIMS:

1. A tape recorder, comprising a stationary base plate, a head mounting plate mounted for reciprocal movement on said base plate, a magnetic head mounted on said head mounting plate, a capstan shaft mounted for rotation on said base plate, a pinch roller movable into or out of contact with said capstan shaft in response to movement of said head mounting plate, and a spring for normally biasing said head mounting plate in a direction to move said pinch roller into contact with said capstan shaft, wherein said pinch roller is mounted at a fixed location of said head mounting plate and the position of said magnetic head for a reproduction mode of said tape recorder is defined by said capstan shaft against which said pinch roller on said head mounting plate is pressed by the biasing force of said spring.

2. A tape recorder as set forth in claim 1, wherein said head mounting plate is mounted for reciprocal linear movement on said base member so as to provide parallel movement of said magnetic head and said pinch roller both on said head mounting plate.

3. A tape recorder as set forth in claim 1 or 2, wherein said pinch roller is supported for rotation on said head mounting plate by means of a mounting bracket

3.- A tape recorder as set forth in claim 1 or 2, wherein said pinch roller is supported for rotation on said head mounting plate by means of a mounting bracket secured to said head mounting plate.

4. A tape recorder as set forth in claim 3, wherein said mounting bracket has a pair of mounting walls extending in parallel toward said capstan shaft and each having a substantially C-shaped recess formed at a central portion at an end thereof adjacent said capstan shaft for receiving an end portion of a shaft of said pinch roller.

5. A tape recorder as set forth in claim 3 or 4, wherein said mounting bracket is made of a synthetic resin material.

6. A tape recorder substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

1. A tape recorder, comprising a stationary base plate, a head mounting plate mounted for reciprocal movement on said base plate, a magnetic head mounted on said head mounting plate, a capstan shaft mounted for rotation on said base plate, a pinch roller movable into or out of contact with said capstan shaft in response to movement of said head mounting plate, and a spring for normally biasing said head mounting plate in a direction to move said pinch roller into contact with said capstan shaft, wherein said pinch roller is mounted at a fixed location of said head mounting plate and the position of said magnetic head for a reproduction mode of said tape recorder is defined by said capstan shaft against which said pinch roller is pressed by the biasing force of said spring, the pinch roller being thereby retained in position on the head mounting plate.

2. A tape recorder as set forth in claim 1, wherein said head mounting plate is mounted for reciprocal linear movement on said base member so as to provide parallel movement of said magnetic head and said pinch roller both on said head mounting plate.