JPS6055543A - Cassette holder mechanism of magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain the application of a miniature rotary damper by setting properly a planetary gear mechanism which connects a cassette holder and the rotary damper and increasing the up-down moving speed of the cassette holder. CONSTITUTION:A planetary gear mechanism 17 consists of gears 15-17. The revolution of a sun gear 15 is transmitted to a rotary damper 14, and the buffing force is applied to a rotor. In case the inserting direction of a cassette 1 is set at X and the lifting direction of a cassette holder 3 is set at Y, the number of revolutions of the damper 14 is obtained as desired by setting properly the coordinates of the rotary shaft of the gear 15 at (a, b) together with lengths of arms 18 and 20 set at l1 and l2 respectively and the number of teeth of gears 15 and 16 set properly respectively. Thus the highest position (X1, Y1) of a pin 19 can be set optionally. Therefore it is possible to increase the move-up speed of the holder 3 and to transmit the movement of the holder 3 to the damper 14. This attains the application of a miniature damper having small buffing force. In addition, a coupling arm can be connected to an optional area of the holder 3. This gives no limitation for position setting of the holder 3 when the cassette is taken out.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a video tape recorder (hereinafter abbreviated as VTR).
The present invention relates to a cassette holder mechanism for a cassette type magnetic recording/reproducing device such as the above.

BACKGROUND ART As shown in FIG. 1, a cassette 1 is inserted into a cassette holder 3 that is movably supported at the top of a VTR main body 2, and is mounted together with the cassette holder 3 at a predetermined position within the VTR main body 2. Or use the cassette holder 3 to
The R main body 2 is lifted upward and taken out. The lifting force for lifting the cassette holder 3 is generally uniformly applied by a spring, so the upward force of the cassette holder 3 is constant regardless of whether the cassette 1 is inserted into the cassette holder 3. A buffer mechanism is required to maintain the temperature.

In the conventional cassette holder mechanism, the arm shaft support of the link mechanism is connected to the side of the link mechanism provided on the side wall of the cassette holder 3 by a gear train or an arm so that the rotational movement of the link mechanism is transmitted. An oil damper is provided.

Then, while the arm of the link mechanism rotates due to the tensile force of the spring and the cassette holder 3 is lifted, the rotation of this arm is transmitted to the oil damper, and the oil damper applies resistance to the link mechanism in the opposite direction to the spring force. Since the force is applied, the upward movement of the cassette holder 3 is damped.

However, this type of conventional cassette holder mechanism
Because the link mechanism of the cassette holder and the oil damper are connected by a gear train, an arm, etc., the rotational motion of the link mechanism cannot be sufficiently accelerated and transmitted to the oil damper. A damper is required.

Additionally, in order to use a small damper with a small buffering force, if the linkage mechanism is configured with a gear train or arm so that the rotational motion of the linkage mechanism is sufficiently accelerated and transmitted to the damper, the linkage mechanism itself will be damaged. Becomes large. Further, there are also restrictions on setting the position of the cassette holder when the cassette is taken out.

Purpose An object of the present invention is to eliminate the above-mentioned drawbacks of the conventional cassette holder mechanism, to sufficiently accelerate the movement of the cassette holder using a small coupling mechanism, and to transmit the motion to the damper, thereby creating a small and small damping force. It is an object of the present invention to provide a cassette/holder mechanism for a magnetic recording/reproducing device which can use a damper and can freely set the position of the cassette holder when taking out a cassette.

Structure Below, the structure of the present invention will be explained along with an embodiment shown in FIGS. 2 and 3.

In FIG. 2, the cassette holder 3 is a box having an opening on one side, into which the cassette 1 is inserted from the top left direction in FIG. Reference numeral 4 denotes a bracket made of an L-shaped flat plate that supports the link mechanism of the cassette holder 3.
It is attached to the chassis of main body 2 with screws.

Further, the brackets 4 are connected to each other via a bar 5 so that no positional deviation occurs.

6 is a first arm, one end of the first arm 6 is rotatably supported by a pin 7 on the side wall 3a of the cassette holder 3, and the other end of the first arm 6 is supported by a bracket 4.
is rotatably supported by a pin 8. 9 is the second
One end of the second arm 9 is connected to the cassette holder 3.
(Int3a is pivotally supported by a pin 10, and the other end of the second arm 9 is rotatably supported by a pin 11 on the bracket 4.
and the second arm 9 constitute a four-bar link, and support the cassette holder 3 so as to be movable up and down with respect to the bracket 4.

A spring 12 is stretched between the center of the second arm 9 and the end of the bracket 4, and the spring 12 applies rotational force to the arm 9 to raise the cassette holder 3.

Reference numeral 13 denotes a damper case fixed to the chassis of the VTR body along with the bracket 4 along the cassette insertion direction, and the damper case 13 has a side wall 13 parallel to the bracket 4.
It has a. 14 is a rotary damper fixed to the damper case 13, and the rotation axis of the rotary damper 14 passes through an opening formed in the damper case side wall 13a and projects from the outside of the side wall 13a perpendicularly to the case side wall 13a. ing.

15 is a sun gear fixed to the rotating shaft of the oil damper 14 protruding from the side wall 13a;
This is a semicircular internal gear formed in the lower half of the outside of a.

A planetary gear 17 is mounted between the sun gear 15 and the internal gear 16 so as to mesh with both gears 15 and 16, and the three gears 15, 16, and 17 constitute a planetary gear mechanism. Then, as the planetary gear 17 revolves around the sun gear 15, the sun gear 15 rotates, and this rotation is transmitted to a rotor (not shown) in the rotary damper 14 and is buffered by the viscosity of oil or the like. Force is applied.

Reference numeral 18 denotes a third arm that transmits the vertical movement of the cassette holder 3 to the planetary gear 17, and one end of the third arm 18 is attached by a pin 19 to one of the four corners of the holder side wall 3a on the side opposite to the cassette insertion opening and on the lower side. The third arm 18 is rotatably sleeved, and the other end of the third arm 18 is rotatably supported on the rotating shaft of the planetary gear 17 .

When the cassette holder 3 moves up and down, the third arm 18 rotates and causes the planetary gear 17 to revolve around the sun gear 15.

A fourth arm 20 holds the planetary gear 17 between the internal gear 16 and the sun gear 15, and one end of the fourth arm 20 is rotatably supported on the rotating shaft of the planetary gear 17. The other end of the fourth arm 20 is rotatably supported on the rotating shaft of the sun gear 15.

In the configuration shown below, the cassette holder 3 on which the cassette 1 is mounted is locked at approximately the same height as the bracket 4, and recording and reproduction of the cassette 1 is performed. At this time, the spring 12 is stretched and applies a lifting force to the cassette holder 3.

When removing the cassette 1, the cassette holder 3 is unlocked by pressing the eject button, and the spring 12 rotates the second arm 9 counterclockwise about the pin 11. Then, the cassette holder 3 is pushed up by the second arm 9 and rises, and the pin 19 rises together with the cassette holder 3.

The third arm 18 then lifts up the planetary gear 17 while rotating clockwise about the pin 19. As a result, the planetary gear 17 moves around the sun gear 15.
The sun gear 15 rotates by rotating clockwise while engaging with the sun gear 15. This rotation is transmitted to the rotor of the rotary damper 14, a damping force is applied to this rotation, and as a result, the upward movement of the cassette holder is damped.

In this way, the upward movement of the cassette holder 3 is damped by the rotary damper 14, the cassette holder 3 smoothly rises to the cassette removal position, and the cassette 1 is removed from the cassette holder 3.

Next, as shown in FIG. 4, the direction in which the cassette 1 is inserted is the X direction, and the direction in which the cassette holder 3 is lifted is
− The XY coordinates are the Y direction and the side wall 1 of the damper case 13.
3a, the sun gear 1 in the operation described above.
Calculate the rotation angle of 5.

FIG. 4 (al indicates a state in which the cassette holder 3 is at the uppermost position, and FIG. 4 (1)) shows a state in which the cassette holder 3 is at the lowermost position.

Now, find the length of the third arm 18! □, the length of the 4th arm addition! . The coordinates of the rotation center of the sun gear 15 are (a.

b), pin 1 when cassette holder 3 is in the uppermost position
If the coordinates of pin 19 are (XIJ,) and the coordinates of pin 19 when cassette holder 3 is at the lowest position are (X2.y2), pin 19 will move from (X2.y2) to (x,,y□). The rotation angle Δθ of the third arm 18 when rising is as follows.

However, L1 = 9 stones, b-yi) ding It is.

The number of teeth of the sun gear 15 and the internal gear 16 are each Z 1
, Z2, the number of revolutions of the sun gear 15 when the cassette holder 3 moves from the lowest position to the most -1- position, that is, the number of revolutions N of the rotor in the rotary damper 14, is as follows.

Therefore, in equations (2) and (2), the coordinates (a, b) of the rotation axis of the sun gear 15, the length of the third arm 18! □,
The length of the fourth arm 20! . , number of teeth of sun gear 15 Z□,
By appropriately setting the number of teeth 72 of the internal gear 16, a desired rotation speed N of the oil damper 14 can be obtained.

Further, the uppermost position cx,,y,) of the pin 19 can also be set arbitrarily.

In this way, in the two-unit embodiment, by appropriately setting the connecting arm between the cassette holder and the planetary gear mechanism and the planetary gear mechanism, the J motion of the cassette holder can be sufficiently accelerated and transmitted to the oil damper. Therefore, a small damper with small buffering force can be used. Also,
Since the connecting arm can be connected to any location on the cassette holder, there are no restrictions on the position setting of the cassette holder when taking out the cassette.

Effects As described in detail above, according to the present invention, there is provided a cassette holder supported vertically movably on the main body of the magnetic recording/reproducing device;
A rotary damper that buffers the vertical movement of the cassette holder is connected via a planetary gear mechanism, and by appropriately setting the planetary gear mechanism, the vertical movement of the cassette holder is sufficiently accelerated and the rotary damper This allows the use of a small rotary damper with low buffering force, and there are no restrictions on the positioning of the cassette holder when taking out a cassette, providing a cassette holder mechanism suitable for miniaturizing magnetic recording and reproducing devices. can do.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the external appearance of a VTR, FIG. 2 is a perspective view showing an embodiment of the present invention, FIG. is a front view showing the state in which the cassette holder is in the uppermost position in the same embodiment, and FIG.
)) is a front view showing a state in which the cassette holder is at the lowest position. 3... Cassette holder, 14... Rotary damper,
15... Sun gear, 16... Internal gear, 17... Planetary gear, I3... Damper case, 18... Third arm. Patent applicant: Ricoh Co., Ltd. Agent: Aohaku Ao and 1 other person

Claims (1)

[Claims] (1) In a cassette holder mechanism comprising a cassette holder supported vertically movably with respect to the main body of the magnetic recording/reproducing apparatus, and a rotary damper for damping the vertical movement of the cassette holder, the rotary wheel and the rotary damper are connected to each other. A cassette holder mechanism characterized in that the vertical movement of the cassette holder is transmitted to the rotary damper via a planetary gear mechanism constituted by an internal gear provided on a base.