JPH0253863B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a cassette storage device for a VTR. (b) Prior Art In recent years, in cassette-type VTRs, the cassette is inserted into the cassette holder inside the main body through the cassette insertion slot on the front of the VTR main body, the cassette is moved together with the cassette holder to the installation position, and the video is recorded at that position. , to perform operations such as playback,
A cassette storage device using a so-called front loading method has been proposed. In the above-described cassette storage device, the cassette holder is always biased in the cassette ejection direction, and the cassette is moved to a predetermined mounting position by the drive mechanism against this bias. In this mounting position, the cassette and cassette holder must be stably held. For this reason, in the past, a worm and a worm wheel were used in the drive force transmission system of the drive mechanism, and by cutting off the driving force of the drive source at the mounting position, a stable cassette mounting state was maintained. However, when a worm and a worm wheel are used in the above-mentioned drive transmission system, there is a drawback that the efficiency of transmitting driving force is reduced. (c) Purpose of the invention The present invention solves the above-mentioned drawbacks, and makes it possible to stably hold a cassette and cassette holder at the cassette mounting position without using a worm or worm wheel in the drive force transmission system. A cassette storage device is provided. (d) Structure of the Invention The present invention provides a structure in which the rotational shaft of a drive gear and the rotational shaft of a drive lever that is driven by a guide pin on the drive gear and drives the cassette holder to the cassette mounting position are different shafts. At the same time, at the cassette mounting position, by arranging the pivot shaft of the drive gear on a line connecting the contact point between the guide pin and the drive lever and the center of the guide pin, the drive lever can be attached to the cassette. This cassette storage device is constructed so that no rotational moment is generated in the drive gear even when the cassette is biased in the ejecting direction, and the cassette and cassette holder are held at the cassette mounting position. (e) Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of the apparatus of this embodiment, FIG. 2 is an outer side view of the left side plate, FIG. 3 is an inner side view of the same, and FIG. 4 is a side view of the drive mechanism. 1 and 2 are a pair of left and right side plates, and 3 , 4, and 5 are a top plate, a bottom plate, and a back plate that connect these left and right side plates, and these constitute a frame. ) is fixed. This frame has cassette holder 6.
is movably supported, and this cassette holder can hold a cassette when it is in a position facing an insertion opening formed on an operation panel (not shown). The cassette holder 6 has bent pieces 6b and 6c rising from both ends of the bottom 6a to position the cassette at a predetermined position. Furthermore, the cassette holder 6
A pair of torsion springs 6 are attached to the side portions 6d, 6d of the
A pair of cassette holding levers 6f and 6f are provided which are urged downward by levers e and 6e to hold the cassette in a predetermined position while the cassette holder 6 is moving. Reference numeral 7 denotes a preventive body for preventing incorrect insertion of the cassette, and cut-outs 3a, 3a, 3b, 3 provided on the top plate 3 .
b is held so as to be rotatable by a predetermined angle. Reference numeral 8 denotes a door that prevents foreign objects from being inserted into the cassette insertion slot, and is rotatably supported on a rotation shaft 8a between the left and right side plates 1 and 2 , and can be opened and closed inward.
It is normally biased toward the closed state by a torsion spring 8b. The opening and closing of this door is controlled by a door opening/closing lever which will be described later. 1a and 2a are L-shaped first guide grooves formed in the left and right side plates 1 and 2 , the bent portions of which are slightly more acute than a right angle; The first guide rollers 6g, 6g are loosely fitted, making the cassette holder 6 movable in the horizontal and vertical directions. 1b, 1b, 2b, 2b are guide pieces formed by bending side plates inward of the first guide groove,
Second guide rollers 6h, 6h provided on the side plates 6d, 6d engage with each other. 9 and 10 are second guide rollers 6h and 6 continuous to the guide piece.
This is an elevating guide plate that guides the guide plate h and is movable up and down along second guide grooves 1c and 2c formed in a dogleg shape on the left and right side plates 1 and 2 , respectively. U-shaped guide portions 9a and 10a each having a width equal to the spacing between the guide pieces are formed on this elevating guide plate. Further, this elevating guide plate has a T-shaped outer shape, and grooves 9b and 10b having a substantially H-shaped cross section are formed in the vertical portion thereof. Therefore, the guide plate is attached by inserting the elevating guide plate through the opening end faces of the second guide grooves 1c and 2c, and fixing the top plate 3 to the left and right side plates 1 and 2 with screws. Further, the elevating guide plates are provided with springs 11 and 12, respectively.
The guide pieces 1b, 1b, 2b, and 2b are normally in a raised position facing the guide pieces 1b, 1b, 2b, and 2b. Reference numerals 13 and 14 are main gears that are supported by first support shafts 1d and 2d that protrude inward from the side plates 1 and 2, respectively, and are driven by a drive mechanism that will be described later.
Guide pins 13a and 14a are provided near the outer periphery of the main gear and are loosely fitted into arcuate third guide grooves 1e and 2e provided in the side plates 1 and 2, respectively. 1f and 2f are second support shafts that protrude outward from the side plates 1 and 2 , and are located at different positions from the first support shafts 1d and 2d that project inward, that is, below. First pivot levers 15 , 15 and second pivot levers 16 , 16 are pivotally supported on the second support shafts, respectively. The first pivot levers 15 , 15 have U-shaped notches 15a, 15a into which the first guide rollers 6g, 6g are loosely fitted via the first guide grooves 1a, 2a, and the third guide grooves 1e, 2e
Approximately L-shaped through holes 15b, 15b are formed through which the guide pins 13a, 14a are loosely fitted, and rotate in conjunction with the rotation of the main gear to move the cassette holder 6. be able to. Coil springs 17 and 17 are stretched between the first and second rotating levers and work to bias the cassette holder 6 downward at the mounting position of the cassette holder 6 . Due to the bias, the first and second pivot levers engage with each other and become integral. 18 is a cross section 6 communicating between the left and right side plates 1 and 2 ;
It is a rectangular drive shaft with drive gears 1 at each end.
8a, 18a are arranged, and these driving gears drive the main gears 13, 14. A joint boss 19 having a protrusion 19a is integrally disposed at the further end of the drive gear 18a at the right end of the drive shaft. Reference numeral 20 denotes a bracket attached to the right side plate 2 , and a drive pulley is attached to this bracket.
1, a driven pulley 24 connected to the motor pulley by a belt 23, and a first intermediate gear 2 disposed coaxially with the driven pulley.
5. Second intermediate gear 2 that meshes with the first intermediate gear
6. A third intermediate gear 27 is disposed coaxially with the second intermediate gear, and a fourth intermediate gear 28 meshes with the third intermediate gear. Reference numeral 29 denotes a stop lever rotatably supported on the second support shaft 2f of the right side plate 2, and a bent piece 15c of the first rotating lever 15 is inserted into a through hole 29a provided in the stop lever 29. Since the two levers are loosely fitted and the coil spring 30 is stretched between the two levers, the two levers are normally integrated, but it is possible to push them apart against the bias of the coil spring 30. And this stop lever 29
A locking piece 29b that engages with a rib 28a provided on the fourth intermediate gear 28 to restrict rotation is provided at the end of the fourth intermediate gear 28.
is provided. A door opening/closing lever 31 opens and closes the door 8 , and is rotatably supported on the third support shaft 1g of the left side plate 1 . An engagement pin 31a that engages with the left end 8c of the door is disposed at the tip of the lever 31, and when the lever 31 is rotated counterclockwise in FIG. 2, the door 8 opens. Further, this lever 31 is formed with a cam portion 31b that can be engaged with a protruding pin 15d provided on the first rotating lever 15 . is controlled to be in the closed state and to be in the open state only when the cassette passes below the door 8 . A third pivot lever 32 is rotatably supported on a fourth support shaft 1h provided on the left side plate, and a coil spring 33 is stretched between one end and the third support shaft 1g. is biased counterclockwise.
Further, the third rotating lever is provided with a cam surface 32a, and since this cam surface 32a engages with the protruding pin 15d, the first rotating lever 15 is biased clockwise. On the other hand, the left side plate 1 is provided with a detection switch 34 for detecting insertion and ejection of a cassette, and this detection switch is controlled by a switch pressing piece 32b provided on the third rotating lever 32. That is, when the first and third rotating levers 15 and 32 rotate to the cassette ejecting position during ejection, the switch pressing piece 32b presses the detection switch 34.
, the drive motor 22 is de-energized, and the fourth intermediate gear 28 stops rotating. In this state, the first rotating lever 15 is biased clockwise by the coil spring 33 via the third rotating lever 32 , so even after the fourth intermediate gear stops, the first rotating lever 15 remains biased.
5 and the drive shaft 18 rotate to cause the cassette to protrude from the cassette insertion slot. Note that when inserting a cassette, contrary to when ejecting it, if you push the cassette against the bias of the coil spring 33,
The first and third rotating levers 15 and 32 rotate counterclockwise and clockwise, respectively, and the switch pressing piece 32
When the driver b presses the detection switch 34, the drive motor 22 is energized. Next, the function of the third rotating lever will be described in detail with reference to FIGS. 5 and 6. FIG. 5 is a left side view immediately after the cassette insertion starts, and FIG. 6 is a left side view immediately before the cassette insertion is completed. In the figures, F1 and F1' are the coil springs 33 in FIGS.
, L1 and L1' are the lengths of the arms of the moment acting on the fourth rotating lever 32, F2 and F2' are the forces acting on the protruding pin 15d, and L2 and L2' are the fourth force acting on the protruding pin 15d. L3 and L3' are the lengths of the moment arms of the movable lever 32 , L3 and L3' are the lengths of the moment arms of the first rotating lever 15 that the protruding pin 15d receives, and F3 and F3' are the forces acting on the first guide roller 6g. , L4, L4' are the arm lengths of the moment acting on the first guide roller, F4, F4' are F3, F
3' shows the component force in the direction of the guide groove. Here, when comparing the state of FIG. 5 and the state of FIG. 6, the biasing force of the coil spring 33 becomes F1<F1', but the length of the moment arm is L1>L1'
becomes. Then, L2<L2', and the protruding pin 15d
The force acting on is expressed as F2=F1×L1/L2, F2′=F1′×L1′/L2′, so if we set F1×L1<F1′×L1′, F2≒
It can be set as F2′. In addition, the forces acting on the first guide roller 6g are, respectively,
F3=L3×F2/L4, F3′=L3′×F2′/L4′. Furthermore, L3>L3', L4>L4', and L3×F2>F2'×L3', but it is set so that F3>F3'. On the other hand, the component forces F4 and F4' of F3 and F3' are F4=F3cosθ1 F4'=F3'cosθ2 (cosθ1<cosθ2), and can be set as F4≈F4'. If F4≈F4' is set as described above, the pressing force when inserting the cassette becomes the resistance force of F4 and F4', respectively, so that the cassette can be inserted with a substantially constant pressing force from the start to the completion of insertion. Next, referring to FIG. 7, the restriction of rotation of the second rotation lever when the cassette mounting is completed will be described in detail. The first rotating lever 16 has a recess 16a and a flat portion 16b that engage with the guide pin 14a of the main gear 14 .
is formed, and the second rotation lever and the main gear are respectively supported on different axes. Therefore, as the cassette loading operation progresses, the guide pin 14a moves from the flat portion 16b on the second rotating lever 16 to the recessed portion 16a, and is completely engaged in the recessed portion 16a when the cassette loading is completed. In this state, the recess 16a and the guide pin 1
The normal line of the contact surface with 4a is directed toward the first support shaft 22d. Therefore, even though the second rotation lever 16 is urged to rotate counterclockwise by the coil spring 17, the force acting on the guide pin 14a is directed toward the first support shaft 2d, so that the main gear 14 is rotated. No moment occurs. (F) Effects of the Invention As described above, according to the present invention, the cassette and cassette holder can be stably held at the cassette mounting position without using a worm or worm wheel in the drive force transmission system, so that the drive It becomes possible to configure the transmission system only with spur gears with high transmission efficiency, and the drive motor can be downsized, which has a great effect.

[Brief explanation of drawings]

The drawings all relate to one embodiment of the present invention.
The figure is an exploded perspective view of the device of this embodiment, FIG. 2 is an outside view of the left side plate, FIG. 3 is a right side view of the same, FIG. 4 is a side view of the drive mechanism, and FIG. The left side view, FIG. 6 is a left side view immediately before the cassette insertion is completed, and FIG. 7 is an explanatory view of the operation of the second rotating lever when the cassette installation is completed. Explanation of main drawing numbers, 13 , 14 ...Main gear, 1
d, 2d...first support shaft, 13a, 14a...guide pin, 16 ...second rotation lever, 16a...recess, 1f, 2f...second support shaft.

Claims (1)

[Claims] 1. Insert the cassette into the cassette holder inside the main body from the cassette insertion opening, move the cassette to the predetermined mounting position while holding it in the cassette holder,
The cassette storage device is configured to perform operations such as recording and reproducing at the mounting position, and includes a drive rotor driven by a drive source, a guide pin disposed on the drive rotor, and a guide pin driven by the guide pin. The cassette holder has a drive lever that drives the cassette holder between a cassette insertion position and a cassette mounting position, and the drive rotor and the drive lever have different rotation axes, and the cassette holder is moved between a cassette insertion position and a cassette mounting position. A cassette storage device characterized in that the rotational axis of the drive rotor is disposed on a line connecting the contact point between the guide pin and the drive lever and the center of the guide pin.