JPH0341294Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a head support plate control device for a tape recorder. (b) Prior Art In order to control the mechanism of a tape recorder in a feather-touch manner, various methods have been proposed that utilize the rotational force of a motor. In particular, when changing from a stop state to a regeneration state, it is necessary to move the head support plate equipped with the magnetic head forward and bring it to the operating position. Conventionally, there has been known a structure in which a driven gear having a toothless portion is engaged with the head support plate so that the head support plate is set to the operating position by one rotation of the driven gear. That is, there has been known a device for moving a head support plate forward from an inactive position to an active position using the rotational force of a motor, for example, as disclosed in Japanese Utility Model Publication No. 16681/1981. The device described in Publication No. 56-16681 is such that an operating pin is provided on a driven gear that rotates in mesh with a driving gear, and a transmission lever and a head support plate in which an elongated hole is loosely fitted into the operating pin are provided. The contacting transmission lever is provided so as to rotate together with an elastic spring interposed therebetween,
When the driven gear rotates by a predetermined angle θ out of 360 degrees, the pair of transmission levers is rotated in one direction via the actuating pin, and the rotational displacement of the pair of transmission levers is used to rotate the head. The support plate is moved forward from the non-operating position to the operating position, and by rotating the driven gear by 360-θ degrees, the pair of transmission levers is again rotated in the other direction via the operating pin. The rotational displacement of the pair of transmission levers is used to move the head support plate backward from the operating position to the non-operating position. When and during meshing of the driven gear with the drive gear, the transmission lever is always engaged with the operating pin, and the force of the spring that urges the transmission lever in one direction is transmitted to the driven gear via the operating pin. is constantly being added to. Therefore, the force of the spring acts as a load and is applied to the driven gear during rotation of the driven gear, making it difficult to rotate the driven gear smoothly. (C) Purpose of the invention This invention is applicable to the stopped state where the first toothless portion of the driven gear faces the drive gear, and the regeneration state where the second toothless portion of the driven gear faces the drive gear. Only in this state, the driven gear is given a rotational force in one direction by the spring, and when the driven gear is meshing with the driving gear and rotating, the force of the spring is not applied to the driven gear and the rotational force is applied to the driven gear in one direction. This allows the driven gear to rotate smoothly. (d) Structure of the invention In order to achieve the above object, the present invention provides a driving gear to which rotational force is applied by a motor, and a driven gear having a cam surface and first and second toothless parts adjacent to each other. and a head support plate that moves forward against the return spring in relation to the cam surface of the driven gear, and in the stopped state, the first toothless portion of the driven gear faces the drive gear, and in the regenerated state, the head supporting plate moves forward against the return spring. In a tape recorder in which a second toothless portion of the driven gear faces the drive gear and moves the head support plate forward by a cam surface to set it in the operating position, the driven gear has first and second inclined surfaces. an annular control ridge having an adjacent annular control ridge, the control ridge abutting a first inclined surface of the control ridge when the driven gear is in the stop position, and the control ridge when the driven gear is in the regeneration position; An activation lever is provided that has a protrusion that abuts against the second inclined surface of the activation lever, and the protrusion of the activation lever collides with the first inclined surface or the second inclined surface by the force of a spring that urges the activation lever in one direction. The structure is such that rotational force is applied to the driven gear only when the gears are in contact with each other. (E) Embodiments Below, embodiments of the device of the present invention shown in the drawings will be described. Reference numeral 1 denotes a reversible motor, which rotates clockwise in play mode and fast forward mode, and counterclockwise in rewind mode. The rotational force of the motor 1 drives an intermediate pulley 3 and a flywheel 4 via a belt 2. An intermediate gear 6 is provided on the same shaft 5 via a slip mechanism on the intermediate pulley 3, and transmission is transmitted while meshing with the intermediate gear 6 on a protruding shaft 8 on a swinging lever 7 that swings around the shaft 5. A gear 9 is pivotally supported. 10,11
is the shaft 1 with the transmission gear 9 disposed in the middle.
A take-up reel stand gear and a supply reel stand gear are rotatably provided at 2 and 13, and as the motor 1 rotates clockwise and the intermediate pulley 3 rotates clockwise in the fast-forward mode, the swing lever 7 swings clockwise, the transmission gear 9 meshes with the take-up reel stand gear 10, and in the rewind mode, the motor 1 rotates counterclockwise and the intermediate pulley 3 rotates counterclockwise. As the swing lever 7 swings counterclockwise, the transmission gear 9 meshes with the supply reel base gear 11, and the tape is fast-forwarded by the rotation of the transmission gear 9. The tape is wound onto the take-up reel for rewinding, or wound onto the supply reel for unwinding. As is well known, a capstan 14 is coaxially provided on the flywheel 4, and a small-diameter drive gear 15 is provided. Reference numeral 16 denotes a driven gear having first and second toothless parts 17a and 17b so as to selectively mesh with the drive gear 15, and is rotatably provided on the shaft 18, as shown by the chain line in the figure. Cam surface 19 on one side
has. The cam surface 19 of the driven gear 16 cooperates with an operating pin 21 set on the lower surface of the head support plate 20 shown in FIG. 8, and the cam surface 19 rotates as the driven gear 16 rotates. As a result, the head support plate 20 is moved in the front and back direction. The head support plate 20 has long holes 22, 22 that are connected to guide shafts 22', 2.
2' to guide its movement.
On the top surface there is an erase head 23 and a recording/playback head 24.
is provided and is always biased to the illustrated inoperative position by a return spring 25. On the other surface of the driven gear 16 , a substantially circular first control protrusion 26 with a partially open part is provided, and an annular second control protrusion 27 is formed.
The control projecting wall 27 has first and second inclined surfaces 28a, 2.
8b are provided adjacent to each other. Reference numeral 29 denotes a first shaft rotatable about a shaft 30 and biased counterclockwise by a spring 31.
A blocking lever, and one end of the blocking lever 29 is connected to a shaft 32.
A rotating lever 3 that is rotatable around the
3, and the other end of the blocking lever 29 faces the protruding shaft 8 of the transmission gear 9. Reference numeral 34 denotes a plunger that enters a trigger operation state when switching from stop mode to regeneration mode, and this plunger 34 rotates the rotation lever 33 counterclockwise during suction operation. Reference numeral 35 denotes a second blocking lever that is rotatable about a shaft 36 and biased counterclockwise by a spring 37. One end of the blocking lever 35 is connected to the first control protrusion 2 of the driven gear 16 .
6, and the other end of the blocking lever 35 faces the protruding shaft 8 of the transmission gear 9. Reference numeral 38 denotes a starting lever that is rotatable about a shaft 39 and biased counterclockwise by a spring 40. A protrusion 38a provided at the tip of the starting lever 38 is connected to the second Control wall 2
It faces the inner surface of 7. Reference numeral 41 denotes a locking lever that is rotatable about a shaft 42 and biased counterclockwise by a spring 43 having a force stronger than the force of a spring 40 biasing the activation lever 38; One end of the locking lever 41 faces the rotating lever 33, and the first other end 41a of the locking lever 41 faces a first locking protrusion 44 provided on the driven gear 16 , and a second The other end 41b faces the second locking protrusion 45 or the first locking protrusion 44 similarly provided on the driven gear 16 . Reference numeral 46 designates a lock lever that is rotatable about a shaft 47 and biased counterclockwise by a spring 48. A lock piece 49 formed at one end of the lock lever 46 is attached to the lower surface of the head support plate 20. The other end 51 of the lock lever 46 faces the raised lock protrusion pin 50, and the other end 51 of the lock lever 46 is connected to the driven gear 16.
It is adapted to face a lock release protrusion 52 provided in the lock release protrusion 52 . Reference numeral 53 denotes an operating lever for manually operating the lock lever 46 from the outside;
It is rotatable around the center. Here, the first toothless portion 17 of the aforementioned driven gear 16
A, the second toothless portion 17b, the first control protrusion 26, the second control protrusion 27, the first locking protrusion 44, the second locking protrusion 45, and the lock release protrusion 52 will be explained a little more. do. That is, as shown in FIG. 1, the stop mode is when the first toothless portion 17a of the driven gear 16 faces the drive gear 15, and at this time, the first control protrusion 2
The second blocking lever 35 is located in the open portion of the locking lever 41 to allow the transmission gear 9 to swing, and the first other end 41a of the locking lever 41 engages with the first locking protrusion 44 to be driven. The rotation of the gear 16 is stopped, and the second control protrusion 27
The protrusion 38 of the activation lever 38 is attached to the first inclined surface 28a of the
a collides and applies a counterclockwise rotational force to the driven gear 16 , and the lock release protrusion 52 is in a position where it does not come into contact with the other end 51 of the lock lever 46. Next, as shown in FIG .
One end of the second blocking lever 35 contacts to prevent the transmission gear 9 from swinging, and the second other end 41b of the locking lever 41 engages with the first locking protrusion 44 to prevent the driven gear 16 from moving. The rotation of the second control protruding wall 27 is stopped, and the second
The protrusion 38a of the activation lever 38 collides with the inclined surface 28b, imparting a counterclockwise rotational force to the driven gear 16 , and the lock release protrusion 52 is in a position where it can come into contact with the other end 51 of the lock lever 46. Note that 55 indicated by a chain line is a cassette. The device of the present invention is constructed as described above, and its operation will be explained below. FIG. 1 shows the stop mode, and the driven gear 16 is given a counterclockwise rotational force by the starting lever 38. However, the driven gear 16 has its first locking protrusion 44 at the first other end 41a of the locking lever 41.
Since the first toothless portion 17a is engaged with the drive gear 15, even if the flywheel 4 and the drive gear 15 rotate in this state, no rotational force is transmitted to the driven gear 16 . Next, when a regeneration operation is performed in the above-mentioned stop mode and the plunger 34 performs a suction operation, the rotating lever 33 rotates counterclockwise about the shaft 32. At this time, the rotating lever 33 engages with one end of the locking lever 41, and the locking lever 41 engages with the spring 4.
3, the first other end 41a of the driven gear 16 is disengaged from the first locking protrusion 44, and as a result, the driven gear 16 is rotated clockwise by the spring 40. It rotates counterclockwise by the activation lever 38 biased counterclockwise and meshes with the drive gear 15. At this time, the rotating lever 33 rotates the first blocking lever 29 clockwise, and the first blocking lever 29
collides with the protruding shaft 8 of the transmission gear 9, and prevents the transmission gear 9 from swinging in the direction of meshing with the take-up reel stand gear 10 as the intermediate pulley 3 rotates clockwise. (See Figure 2). However, even though the suction operation of the plunger 34 is completed thereafter, the driven gear 16 is moved to the first locking protrusion 4 by the rotational force of the drive gear 15 rotating clockwise.
4 kicks up the first other end 41a of the locking lever 41 and rotates it counterclockwise. After passing the first locking protrusion 44, the locking lever 41 is rotated counterclockwise again by the spring 43, and
Further, the first blocking lever 29 is also rotated back counterclockwise by the spring 31. On the other hand, the second blocking lever 35 collides with the first control protrusion 26 of the driven gear 16 and rotates clockwise, and the other end collides with the protruding shaft 8 of the transmission gear 9 to prevent its swinging. Further, the cam surface 19 of the driven gear 16 is engaged with the operating pin 21 of the head support plate 20 shown in FIG. 8 (see FIG. 3). Therefore, while the driven gear 16 is rotating, the transmission gear 9 is prevented from swinging by the second blocking lever 35, and at the same time, the cam surface 19 and the operating pin 21 are prevented from swinging.
Due to the engagement relationship, the head support plate 20 moves forward against the spring 25. and driven gear 1
When the second toothless portion 17b of 6 faces the drive gear 15, the rotational force to the driven gear 16 is cut off, and at the same time, the first locking protrusion 44 of the driven gear 16 engages the locking lever 4.
The protrusion 3 at the tip of the activation lever 38 engages with the second other end 41b of the activation lever 38 to stop its rotation.
8a comes into contact with the second inclined surface 28b of the second control projecting wall 27. Then, the head support plate 20 is set to the fully advanced operating position via the operation pin 21 that has been following the cam surface 19, and at this time, the lock pin 50 of the head support plate 20 is moved completely forward.
is locked by the lock piece 49 of the lock lever 46 to maintain the operating position of the head support plate 20 (see FIG. 4). In this state, the recording/reproducing head 24 on the head support plate 20 is brought into contact with the tape in the cassette 55,
You can get playback mode. Next, in the regeneration mode shown in FIG. 4, if the plunger 34 performs the suction operation again, the rotating lever 33 is rotated counterclockwise, and the locking lever 41 is rotated clockwise accordingly, causing the second The other end 41b
is disengaged from the first locking protrusion 44, and the protrusion 38a at the tip of the activation lever 38 is moved to the second inclined surface 28 of the second control protrusion 27 by the biasing force of the spring 40.
b is pressed, and as a result, the driven gear 16 slightly rotates counterclockwise, engages with the drive gear 15 from its second toothless portion 17b, and rotates counterclockwise (see FIG. 5). This rotation of the driven gear 16 causes the lock release protrusion 52 to collide with the other end 51 of the lock lever 46, causing the lock lever 46 to rotate clockwise. Therefore, the lock piece 49 of the lock lever 46 is separated from the lock pin 50 of the head support plate 20 (see FIG. 6), and the operating pin 21 is opposed from the maximum diameter part to the minimum diameter part of the cam surface 19. Therefore, the head support plate 20 is connected to the spring 2.
It moves backward from the operating position and returns to the non-operating position by the applied force No. 5. The first toothless portion 17a of the driven gear 16 faces the drive gear 15. At this time, the second
The activation lever 3 is attached to the first inclined surface 28a of the control projecting wall 27.
Since the protrusions 38a of No. 8 collide with each other, a counterclockwise rotational force is applied to the driven gear 16 by the starting lever 38 before the power transmission from the driving gear 15 is stopped. However, during this time, the plunger 34 is kept in a suction operation, and the locking lever 41 continues to rotate clockwise.
The locking protrusion 45 is connected to the second other end 41 of the locking lever 41.
b, and the rotation of the driven gear 16 is stopped (see FIG. 7). Next, when the plunger 34 is deactivated after such a state, the locking lever 41 is activated via the rotation lever 33.
rotates back counterclockwise, the second other end 41b is disengaged from the second locking protrusion 45, and the driven gear 16 is rotated counterclockwise by the biasing force of the starting lever 38. Rotate to. The rotation of the driven gear 16 is performed within the toothless range of the first toothless portion 17a, and the first locking protrusion 44 engages with the first other end 41a of the locking lever 41. It then stops and enters the stop mode shown in FIG. (f) Effects of the invention Since the device of the invention is configured as described above, the first tooth-missing portion of the driven gear is in a stopped state facing the drive gear, and the second tooth-missing portion of the driven gear is in a stopped state facing the drive gear. Only in the regenerating state where the teeth face each other, the driven gear can be given a unidirectional rotational force by the spring, and as a result, when the driven gear is meshing with the driving gear and rotating, the spring Since the force is not applied to the driven gear, it does not become a load, and the driven gear can be rotated smoothly. However, the present invention is extremely practical as it is implemented in a small tape recorder that uses a driving gear and a driven gear that are rotated by the rotational force of a motor to switch from a stop mode to a playback mode and from a playback mode to a stop mode. It is.

[Brief explanation of the drawing]

The figures show the device of the present invention. Fig. 1 is a plan view in stop mode, Fig. 2 is a plan view immediately after plunger suction from stop mode, and Fig. 3 is the meshing of the driven gear and driving gear during transition to regeneration mode. State plan, 4th
The figure is a plan view of the regeneration mode, Fig. 5 is a plan view of the state immediately after plunger suction from the regeneration mode, Fig. 6 is a plan view of the engaged state of the driven gear and drive gear during the transition to the stop mode, and Fig. 7 is a plan view of the stopped state. FIG. 8 is a plan view of the state immediately before the mode, and is a plan view showing the relationship between the head support plate and the driven gear. DESCRIPTION OF SYMBOLS 1... Motor, 15... Drive gear, 16 ... Driven gear, 19... Cam surface, 17a... First missing tooth part, 17b... Second missing tooth part, 34... Plunger, 20... Head Support plate, 21... actuation pin,
27...Control projecting wall, 28a, 28b...First and second inclined surfaces, 33...Rotating lever, 38...Starting lever, 38a...Protrusion, 40...Spring,
41...Latching lever, 43...Spring, 44
...Latching protrusion.

Claims (1)

[Scope of utility model registration request] a driving gear to which a rotational force is applied by a motor; a driven gear having a cam surface and first and second toothless portions adjacent to each other; and a head support plate that moves forward, in a stopped state, the first toothless portion of the driven gear faces the drive gear, and in the regenerated state, the second toothless portion of the driven gear faces the drive gear, and supports the head. In a tape recorder in which a support plate is moved forward by a cam surface and set to an operating position, the driven gear is provided with an annular control projecting wall having first and second inclined surfaces adjacent to each other, and the driven gear is stopped. an activation lever having a protrusion that abuts against a first inclined surface of the control protrusion when the driven gear is in the normal position and a second inclined surface of the control protrusion when the driven gear is in the regeneration position; , so that rotational force is applied to the driven gear only when the protrusion of the starting lever collides with the first inclined surface or the second inclined surface by the force of the spring that biases the starting lever in one direction. A head support plate control device for a tape recorder, characterized in that: