JPH041940B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a loading mechanism for a video tape recorder suitable for an ultra-small VTR such as an 8 mm video tape recorder. (b) Prior Art Cassette-type VTRs require a loading mechanism that pulls out the tape from inside the cassette and wraps it around a guide cylinder at a predetermined angle. Among these loading mechanisms, in the so-called M loading method, the tape guide for pulling out the tape defines the tape wrapping angle around the guide cylinder when loading is completed, so that the tape guide is pressed against the positioning means when loading is completed. Must be accurately positioned. For this reason, in conventional mechanisms, the support member that supports the tape guide is loosely fitted into the loading arm so that it can slide in the loading direction, and is strung between the two to allow the loading arm to overhang during loading. This absorbs the stroke and presses the tape guide against the positioning means. However, in this conventional mechanism, a loose fitting pin and a spring must be provided at the connecting portion between the loading arm and the support member, making it difficult to simplify and downsize the loading mechanism. (c) Purpose The present invention solves the above-mentioned drawbacks and provides a loading mechanism for a video tape recorder that is suitable for miniaturization. (D) Structure The present invention relates to a video tape recorder in which a tape is pulled out from a cassette and wound around a guide cylinder at a predetermined angle for recording and playback. loading means comprising a first link connected at substantially the center thereof, a second link connected to the first link, and a tape guide connected to the second link; and positioning the tape guide in a loading completed state. loading means for pressing the tape guide against the positioning means by rotationally urging the first and second links in a direction in which they mutually extend when loading is completed; It is a mechanism. (E) Embodiment An embodiment of the present invention will be described below with reference to the drawings. The mechanism of this embodiment can be roughly divided into loading mechanism,
and mode setting mechanism. First, the loading mechanism will be explained. FIG. 1 is a plan view of the loading mechanism in eject mode, and FIG. 2 is a left side view of the loading mechanism in play mode. A guide cylinder 1 is mounted obliquely on a chassis 2, and a guide protrusion 3 is integrally disposed on the lower side of the guide cylinder for guiding a part of a loading means, which will be described later, during loading. In addition, the pair of left and right first support shafts 4, 4 have a pair of first support shafts 4, 4.
Drawer arms 5, 5 are rotatably attached, and a pair of first
Pull-out pins 6, 6 are arranged. This first pull-out pin is located in the notch 7a formed in the cassette 7 in the eject mode, and when the tape 8 is pulled out, the first pull-out arm is rotated by 90 degrees.
Pull the tape 8 out of the cassette 7 . A second support shaft 9 is disposed near the first support shaft on the left side, and a second drawer arm 11 having a second drawer pin 10 disposed at its tip is pivotally supported on this second support shaft. . This second pull-out pin is also located within the notch in the eject mode and stop mode. A pair of loading arms 12, 12 are disposed coaxially with the first support shaft, and a first loading link 1 is disposed at the tip of the loading arm.
3, connected to the center of 13 . One end of a pair of second loading links 14, 14 is connected to one end of the first loading link, and the other end of the second loading link is connected to a connecting pin 15,
A pair of left and right sliders 16, 16 are attached via 15. This connecting pin protrudes downward through the second loading link, and engages with a pair of guide grooves 17a, 17a formed in the guide plate 17 disposed on the chassis, and is at the unloading position. and the loading position. Further, as shown in FIG. 3, a leading guide block 18 is rotatably disposed on the left slider, and a tape guide 18a and an inclined pin 18b inclined in the direction of the tape guide are provided on the leading guide block 18. There is. Further, the guide lock and the slider are connected by a connecting pin 18c, which projects downward and engages with the guide groove. Further, the tape guide protrudes downwardly through the leading guide block and engages with the guide groove. On the other hand, a leading guide block 19 is similarly disposed on the right slider via a connecting pin 19c, and an inclined pin 1 is connected to the tape guide 19a.
The direction of inclination of 9b is opposite to that of the left side. Fixing blocks 20, 20 for fixing the pair of tape guides at the loading completion position are arranged at the ends of the guide plate. Further, a pair of protruding pins 13a, 13a are provided below the other end of the first loading link, and the protruding pins are inserted into the notches 21a of the pair of U-shaped guides 21 , 21 in the unloading state. , 21a. Elastic wire-like guide rods 22, 22 are disposed on the open end side of this notch, and guide the protruding pins continuously to the notches 21a, 21a when the tape is pulled out, and guide the protruding pins when the tape is stored. Guide the protruding pin into the notch. Further, trapezoidal guides 23, 23 are arranged near the guide rods, and guide rods 22, 22
The protruding pin is guided continuously. Furthermore, the second support shaft and the third support shaft 2 are provided near the trapezoidal guide.
A pair of rotating pieces 25 and 26 are disposed, respectively, and are pivoted to the trapezoidal guide 4, and are biased by torsion springs 27 and 27, respectively, in a direction to press against the trapezoidal guide. Immediately before the loading is completed, the projecting pin contacts the rotating piece and rotates a little, pressing the tape guide against the fixed block by the biasing force of the torsion spring. The second drawer arm and the left loading arm are connected by a connecting lever 11a. The back tension lever 28 is rotatably supported on a fourth support shaft 29, and has a tension detection pin 2 at one end.
8a, and a spring 30 on one of the other ends that biases the tape 8 in a counterclockwise direction to apply tension to the tape 8.
Also, the brake belt 31 is attached to one of the other ends.
One end is fixed. This brake belt is wound around a pulley on the supply side of the supply and take-up reel stands 32 and 33, and the other end is fixed to the chassis 2. Further, the back tension lever is restricted from rotating counterclockwise by one end of the first drawer arm. The supply and take-up reel stands are driven by a reel stand drive mechanism. This reel stand drive mechanism includes a reel motor 34, a drive gear 35 disposed on the drive shaft of the reel motor, an intermediate gear 36 that meshes with the drive gear, and a rotatable idler disposed coaxially with the intermediate gear. It is composed of a lever 37 and an idler gear 38 disposed on the idler lever and always meshing with the intermediate gear, but since this structure has no special features, a detailed explanation will be omitted. Further, brake levers 39, 39 having brake shoes 39a, 39a at one end are arranged close to each of the reel stands, respectively, and these brake levers are configured to be controlled by brake release bins 40, 40, which will be described later. has been done. On the other hand, a pinch roller 42 is placed on one end of a pinch roller lever 41 that is pivotally supported on a fifth support shaft 24, and this pinch roller is connected to a capstan 43.
It is now possible to pressure-weld. An engagement pin 44 protrudes from the other end of the pinch roller lever through an arcuate notch 2a of the chassis 2 , and is controlled by a pinch roller crimping mechanism to be described later. The cassette can be raised and lowered by a cassette holder mechanism (not shown), and is positioned by cassette positioning pins 45, 45, 46, and 46 when installed. Next, the operation of the above-mentioned loading mechanism will be explained with reference to FIGS. 1, 4, and 5. First, the eject mode will be explained. When the cassette 7 is inserted into a cassette holder (not shown) and the cassette holder is pushed down to a predetermined position, the cassette holder is locked and the cassette is held in a predetermined position by the positioning pins 45, 45, 46, 46. Positioned. In this state, as shown in FIG. 1, the first pull-out pins 6, 6, the second pull-out pin 10, the leading guide blocks 18 , 19 , and the pinch roller 42 are located in the notch 7a of the cassette. Further, the connection points of the first loading links 13 , 13 and the second loading links 14, 14 are bent, and the protruding pins 13a, 13a of the first loading links are connected to U-shaped guides 21, 21, respectively. The notches 21a, 21a of the two are connected to each other. Also, in this state, the brake levers 39 , 3
9, the brake state is released by the brake release pins 40, 40. When the cassette is installed in a predetermined position, a cassette detection switch (not shown) is activated, and a loading motor, which will be described later, is energized. This energization causes the first drawer arms 5, 5 to move approximately outward from the cassette around the first support shafts 4, 4, respectively, as shown in FIG.
Rotate 90°. As a result, the first loading operation is performed, and the tape 8 is slightly pulled out by the first pull-out pins 6, 6, which becomes the stop mode. In this stop mode, the brake release pin moves downward from the position shown in FIG. 1, so that the brake shoes 39a, 39a are engaged with the pulleys of the supply and take-up reel stands 32, 33.
In addition, in this mode, the tape 8 is attached to the guide cylinder 1.
There is no contact with the cassette case. When fast forwarding and rewinding operations are performed in this stop mode, the tape 8 continues to run in this state. Note that at this time, the brake lever is released. Next, when a playback operation is performed from the stop mode, a second loading operation is performed in which the lead guide blocks 18 and 19 pull out the tape 8 and wrap it around the guide cylinder 1 by about 210 degrees. This operation will be explained in detail regarding the right loading mechanism. First, the loading arm 12 rotates clockwise. This rotation causes the first loading link 13 to rotate clockwise about the protruding pin 13a that engages with the U-shaped guide 21 , pushing the second loading link 14 upward in FIG. Therefore, the connecting pin 15 that engages with the guide groove 17a and the lower end of the tape guide 19a move from the bottom to the top in the figure along this guide groove while pulling out the tape 8, and the leading guide block 19 pulls out the tape 8. . When the loading arm further rotates, the protruding pin escapes from the notch 21a of the U-shaped guide, contacts the guide rod 22, and is guided for a short period of time. When the loading arm further rotates, the protruding pin is separated from the guide rod and guided into engagement with the trapezoidal guide 23. Furthermore, the connection points of the first and second loading links 13 and 14 are engaged with and guided by the guide protrusion 3. The trapezoidal guide and the guide protrusion restrict the positions of the protruding pin and the connection point, respectively, so that the first and second loading links do not bend each other, and the driving force of the loading arm is directed against the leading guide block. It is intended to communicate to people. Then, when the leading guide block moves to a position close to the fixed block 20, the protruding pin separates from the trapezoidal guide and comes into contact with the rotating piece 26, causing this rotating piece to resist the bias of the torsion spring 27. At the same time, the connection point is also separated from the guide protrusion. Further, when the leading guide block reaches the end of the guide groove 17a and the tape guide 19a and the inclined pin 19b engage with the fixed block as shown in FIG.
The loading arm stops rotating. In this state, the first loading link is urged to rotate clockwise by the rotating piece, so that the leading guide block is pressed against the fixed block side and is fixed in position, and the tape 8 is moved to the guide cylinder 1. The wrapping angle is accurately defined. On the other hand, in conjunction with the rotation of the loading arm, the pinch roller arm 41 also rotates clockwise, and after the leading guide lock comes into contact with the fixed block, the pinch roller 42 moves to the cap stamp 43.
The play mode is entered and playback operations are performed continuously. Further, the second drawer arm 11 is connected to the connecting lever 11.
Left loading arm 1 connected to a
2, the tape 8 is rotated to the position shown in FIG. 4, and the tape 8 is mounted on the tension detection pin 28a. Next, when a recording operation is performed from the stop mode, a second loading is performed in the same way as during a playback operation, but even after the second loading is completed, the pinch roller arm separates the pinch roller from the capstan. The recorder is stopped at a position where it is kept in the same state, and this state is set as recording standby mode. When a pause release operation is performed from this recording standby mode, the pinch roller 42 presses against the capstan 43, resulting in the state shown in FIG. 5, and the recording mode is entered. Further, when a stop operation is performed from the recording or reproducing mode, unloading is performed, which is completely opposite to the second loading operation described above, and the stop mode shown in FIG. 4 is entered. Further, when an eject operation is performed from this stop mode, the cassette holder is unloaded in an operation completely opposite to the first loading operation, resulting in the eject mode shown in FIG. 1, and the cassette holder is raised continuously. Next, a mode setting mechanism that drives the aforementioned loading mechanism and also sets a mode will be explained. 6 is a plan view of the mode setting mechanism in the play mode, and FIG. 7 is a sectional view of the same on the right side. The mode setting mechanism is arranged on the lower surface of the chassis 2 . Motor gear 1 coupled to loading motor 100
01 is in mesh with a loading gear 102a provided on the outer periphery of the mode setting cam 102 . This adjustment cam is pivotally supported by a fifth support shaft 103 protruding from the lower surface of the chassis, and in addition to the loading gear, a brake cam 102b that controls the brake lever, a spirally cut loading Arm drive cam 102c, first drawer arm drive cam 102d, and pinch roller cam 102e
It has an integrated structure. A fan-shaped gear 105 is pivotally supported on the sixth support shaft 104, and an engagement pin 105 disposed on the fan-shaped gear
a is engaged with the loading arm drive cam. Further, this fan-shaped gear includes a first intermediate gear 10.
6 is engaged. This first intermediate gear is pivotally supported by a pair of seventh support shafts 107, 107, and a pair of second intermediate gears 1 that mesh with each other are mounted on the seventh support shafts.
08,108 are pivoted. One of the first intermediate gear and the second intermediate gear is integral with each other. As shown in FIG. 7, a pair of gear boxes 109 , 109 are disposed coaxially with the pair of first support shafts 4, 4 and on the lower surface of the chassis. A cylindrical boss 109a is formed at the center of this gearbox, and this boss bears the first support shaft inwardly, and a first driven gear 110 is supported outwardly. The first driven gear is integrally connected to the loading arm and meshes with the second intermediate gear. On the other hand, a second driven gear 111 is integrally coupled to the right first support shaft together with the first pull-out arm. This second driven gear is formed with a cutout portion 111a in which the teeth of the second driven gear are partially cut out, so that the second driven gear can mesh with the loading gear. Further, a pair of foils 1 are attached to the pair of first support shafts.
12 and 113 are connected, and both wheels are connected by a connecting shaft 114. A portion of the right wheel 112 is missing, and a rotation regulating pin 115 is installed on the lower surface of the gearbox.
This restricts the rotational position of the first drawer arm when the first drawer arm is drawn out. Further, an engagement pin 112a is disposed on the right side wheel and can be engaged with the first drawer arm drive cam. Further, the left wheel 113 is urged counterclockwise by a spring (not shown), and the right wheel is therefore urged clockwise. Further, a rotatable brake control lever 116 is engaged with the brake cam, and this brake control lever is engaged with a slide lever 117 on which the brake release pin is arranged. This slide lever has through holes 117a and 117b formed therein, and a loose fitting pin 11 fixed to the chassis.
8 and 119 are loosely fitted into each other, and can be slid by rotating the brake control lever. Next, the operation of the mode setting mechanism described above will be explained with reference to FIGS. 6, 8, and 9. As shown in FIG. 8, the mode setting cam 102 sets each mode by rotating within a range of 0° to 270° with the eject mode as a starting point. First, in the eject mode, the first drawer arm 5 and loading arm 12 are in the retracted state, as shown in FIG. Further, the brake control lever 116 is engaged with the outer periphery of the brake cam 102b, and the brake on the reel stand is released. Next, when the cassette is installed, the loading motor 100 is energized and the mode setting cam is rotated counterclockwise from the eject mode position. This rotation causes the second driven gear 111 meshing with the loading gear 102a to rotate clockwise, and the first drawer arm 5 rotates clockwise while pulling out the tape and performing the first loading. When the second driven gear rotates to a predetermined position, the loading gear faces the cutout portion 111a of the second driven gear, so that the meshing is released. however,
Since the foil 112 is biased clockwise as described above, the first drawer arm rotates continuously and stops when the foil engages with the rotation restriction pin. Furthermore, the mode setting cam is moved from the eject position.
When the loading motor is rotated by 75 degrees, the loading motor stops and enters the stop mode as shown in FIG. In this state, the brake control lever rotates counterclockwise to engage with the recess of the brake cam, thereby pressing the brake lever 39 against the reel stand. Also,
In this state, the loading arm drive cam 102
Since the diameter of c is the same as in the eject mode, the fan-shaped gear 105 is not displaced and the loading arm 1
2 is still in the stored state. When fast forwarding and rewinding operations are performed in this stop mode, the mode setting cam rotates 30 degrees clockwise, that is, toward the eject mode.
Therefore, the brake control lever rides on the outer periphery of the brake cam and rotates clockwise, so that the brake of the reel stand is released. Further, when a recording operation is performed in the stop mode, the mode setting cam is rotated 150 degrees counterclockwise, and the recording standby mode is entered. Due to this rotation, the diameter of the loading arm drive cam becomes smaller continuously, and the fan-shaped gear rotates clockwise.
Therefore, since the first and second intermediate gears 106 and 108 rotate counterclockwise, the first driven gear 110 and loading arm 12 rotate clockwise.
A second loading is performed. Furthermore, the brake applied to the reel stand is released by rotation of the mode setting cam. In this recording standby mode, the pinch roller and capstan are kept close to each other but separated by a pinch roller cam, which will be described later. Further, when a pause release operation is performed in this recording standby mode, the mode setting cam further rotates 45 degrees counterclockwise, and the play mode shown in FIG. 6 is entered. Note that during this 45° rotation, the diameter of the loading drive cam does not change, so the position of the loading arm does not change. Further, when a playback operation is performed in the stop mode, the mode setting cam does not stop in the recording standby mode but continuously rotates to the play mode position. Further, when an eject operation is performed in the stop mode, the mode setting cam rotates clockwise. At this time, the first drawer arm drive cam 102d is connected to the engagement pin 11 provided on the foil 112.
2a, and together with this wheel, the second driven gear is slightly rotated counterclockwise. For this reason,
Loading gear 102a of the mode setting cam
meshes with the second driven gear, as shown in FIG.
The first drawer arm is in a retracted state. Incidentally, the unloading operation from the play mode to the stop mode is performed in the exact opposite manner to the second loading operation. Next, the pinch roller crimping operation will be explained.
Figure 10 is a perspective view of the pinch roller crimping mechanism,
1 to 13 are explanatory diagrams of the operation of the pinch roller crimping mechanism in the stop mode, recording standby mode, and play mode, respectively, and the engagement pin 44 of the pinch roller lever 41 passes through the notch of the chassis 2 to the pinch roller crimping lever 120. through hole 120
It fits loosely into a. This pinch roller pressure bonding lever is pivotally supported by the eighth support shaft 121, and the return spring 1
22 in a counterclockwise direction. An engagement lever 123 is also pivotally supported on this eighth support shaft, and is capable of engaging with the pinch roller cam 102e. The pinch roller pressure lever and the engagement lever are biased in opposite directions by a pressure spring 124. As shown in FIG. 11, in the stop mode, the pinch roller 102e and the engagement lever 123 are separated, and the pinch roller lever 41 is in the return position by the return spring 122. As shown in FIG. 12, in the recording standby mode, when the mode setting cam rotates counterclockwise, the engagement lever engages with the pinch roller cam and rotates clockwise, so that the pinch roller cam rotates clockwise. The roller is close to the capstan 43. Further, as shown in FIG. 13, in the play mode, the engagement lever engages with the maximum diameter portion of the pinch roller cam, so the pinch roller comes into contact with the capstan. At this time, the engagement lever rotates a little with respect to the pinch roller pressing lever, and the pinch roller is pressed against the capstan with a predetermined pressing force by the action of the spring. (F) Effects As described above, according to the present invention, the loading mechanism itself does not have a complicated overstroke absorbing means, and by applying external force, the loading mechanism can be simplified and an ultra-compact VTR can be realized. .

[Brief explanation of drawings]

The drawings all relate to one embodiment of the present invention.
The figure is a plan view of the loading mechanism in eject mode, Figure 2 is a left side view of the same in play mode, Figure 3 is a cross-sectional perspective view of the left leading guide block, Figure 4 is an explanatory diagram of the operation of the loading mechanism in stop mode, 5 is an explanatory diagram of the same operation in the play mode, FIG. 6 is a plan view of the mode setting mechanism in the play mode, FIG. 7 is a right sectional view of the same in the play mode, and FIG. 8 is an explanatory diagram of the same operation in the eject mode. FIG. 9 is an explanatory diagram of the same operation in stop mode, FIG. 10 is a perspective view of the pinch roller pressure bonding mechanism, FIG. 11 is an explanatory diagram of the same operation in stop mode, FIG. 12 is an explanatory diagram of the same operation in recording standby mode, and FIG. 13 is an explanatory diagram of the same operation in stop mode. is an explanatory diagram of the same operation in play mode. Explanation of main drawing numbers, 1...Guide cylinder, 1
2, 12...Loading arm, 13 , 13 ...
...1st loading link, 14, 14...2nd
Loading link, 16, 16...slider,
18, 19 ... Leading guide block, 20, 20
... Fixed block, 25, 26 ... Rotating piece, 2
7, 27... Torsion spring.

Claims (1)

[Claims] 1. In a video tape recorder that records and plays a tape by pulling it out from a cassette and wrapping it around a guide cylinder at a predetermined angle, the loading arm is pivotally supported on a support shaft, and the approximately central portion thereof is connected to the rotating end of the loading arm. loading means comprising a first link connected to the first link, a second link connected to the first link, and a tape guide connected to the second link; positioning means for positioning the tape guide in a loading completed state; a loading mechanism for a video tape recorder comprising biasing means for pressing the tape guide against the positioning means by rotatably biasing the first and second links in a direction in which they mutually extend in a completed state.