JPH034988Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is used in a one-motor central capstan type magnetic recording tape traveling device equipped with a first reel shaft and a second reel shaft. The present invention relates to a reel shaft drive changing device for a magnetic recording tape running device that changes between driving by a shaft and driving by a second reel shaft.

In a conventional central capstan type magnetic recording tape running device equipped with a first reel shaft and a second reel shaft, each of the first reel shaft and the second reel shaft is driven by a drive belt or a gear train. The capstan is connected to a bidirectional electric motor rotatable with the same characteristics in one direction and the other direction, which drives the capstan.

The first reel shaft and the second reel shaft having such a configuration include a cylindrical drive member that is constantly driven and rotated by a drive belt or a gear train, and a cylindrical drive member that is rotatable concentrically with respect to the drive member. A reel hub mounting member is provided to which the reel hub is mounted. A plurality of portions each having a planar shape that is part of a spiral are formed on the outer circumferential surface of the reel hub mounting member, and the outer circumferential surface faces the inner circumferential surface of the drive member. A ball or roller is disposed between each of the portions of the outer peripheral surface shaped like a part of the spiral and the inner peripheral surface. Note that the spiral shapes of the first reel shaft and the second reel shaft are such that one has a right-handed spiral and the other has a left-handed spiral. When the capstan rotates in one direction, the balls or rollers on the first reel shaft slide against the inner circumferential surface of the driving member and move to the spiral-shaped portion with a larger diameter. The reel hub mounting member is held between the surface and the outer peripheral surface of the reel hub mounting member, and the reel hub mounting member is rotated in one direction together with the driving member by the driving force of the bidirectional electric motor. At this time, on the second reel shaft, the balls or rollers move to the smaller diameter part of the spiral shape of the reel hub mounting member due to sliding contact with the driving member, and the inner peripheral surface of the driving member and the outer periphery of the reel hub mounting member are moved. It spins idly between the surface and the surface. Therefore, the magnetic recording tape runs from the second reel hub mounted on the second reel shaft to the first reel hub mounted on the first reel shaft. This is reversed when the capstan is rotated in the other direction. In the conventional reel shaft drive changing device of a magnetic recording tape running device having such a configuration, when oil or dust enters between the inner circumferential surface of the drive member and the outer circumferential surface of the reel hub mounting member, the take-up reel Disadvantages of frictional engagement between the ball or roller on the reel shaft that functions as the shaft and the reel hub mounting member and the rotation of the ball or roller on the reel shaft that functions as the supply reel shaft. There is. When such defects occur, the magnetic recording tape may become loose between the capstan and the first reel shaft or between the capstan and the second reel shaft, and this slack may damage the magnetic recording tape. Resulting in. Further, the above devices using rollers or balls have the disadvantage that they are complicated in construction and relatively expensive to manufacture and assemble.

This invention was made based on the above circumstances, and the purpose of this invention was to develop the first magnetic recording tape.
Not only can the change between driving by the first reel shaft and driving by the second reel shaft be performed reliably without being hindered by the intrusion of oil or dust, but it also has a simple configuration and is easy to manufacture. Another object of the present invention is to provide a magnetic recording tape running device that requires relatively low assembly costs.

A first reel shaft 10 and a second reel shaft 12 rotatably provided on a substrate not shown in FIG.
It is shown. The first reel shaft 10 includes a first reel hub mounting portion 16 to which a first reel hub 14 is mounted. Also, the second reel shaft 12
includes a second reel hub mounting section 20 to which a second reel hub 18 is mounted. A first gear 22 is concentrically fixed to the first reel hub mounting part 16, and the first gear 22 rotates together with the first reel hub mounting part 16. A second gear 24 is concentrically fixed to the second reel hub mounting section 20, and the second gear 24 rotates together with the second reel hub mounting section 20.

FIG. 1 also shows a capstan 26 that is rotatably provided on a substrate (not shown). The capstan 26 is arranged below a substantially intermediate position between the first reel shaft 10 and the second reel shaft 12. A third gear 28 and a flywheel 30 are concentrically fixed to the capstan 26.
Therefore, the third gear 28 and the flywheel 30 are
It rotates together with the capstan 22.

The first reel hub 14 has a magnetic recording tape 3
One end of the second reel hub 1 is wound around the second reel hub 1.
The other end of the magnetic recording tape 32 is wound around the tape 8 . The magnetic recording tape 32 is in contact with the outer peripheral surface of the capstan 22 between the first reel hub 14 and the second reel hub 18.

An annular groove is formed on the outer peripheral surface of the flywheel 30 so that the flywheel 30 functions as a pulley. A drive belt 33 is hooked to the annular groove of the flywheel 30, and the drive belt 33 is also hooked to the output shaft of a bidirectional electric motor 34 that can rotate with the same characteristics in one direction and the other direction. .
Therefore, when the bidirectional electric motor 34 rotates in one direction as shown by arrow A in FIG.
0, the third gear 28 and the capstan 26 are also
It rotates in one direction as shown by arrow B in the figure. Also, when the bidirectional electric motor 34 rotates in the other direction, which is the direction opposite to the direction indicated by arrow A in FIG.
rotates in the other direction, which is opposite to the direction indicated by arrow B in FIG.

As shown in FIG. 1, a substantially intermediate portion of a swinging member 36 having one end and the other end extending radially outward of the capstan 26 is swingably attached to the capstan 26. A fourth gear 38 is rotatably attached to one end of the swinging member 36, and the fourth gear 38 meshes with the third gear 28. Further, a fifth gear 40 is rotatably attached to the other end of the swinging member 36, and the fifth gear 40 meshes with the third gear 36.

In this embodiment, a pin 42 is implanted at one end of the swinging member 36, as shown in particular detail in FIG. And the fourth gear 38 is attached to the pin 42.
are rotatably mounted concentrically. The head 44 of the pin 42 has a larger diameter than the body 46 of the pin 42. A biasing means 48 is disposed between the head 44 of the pin 42 and the lower surface of the fourth gear 38, as shown in FIG. Biasing means 4
As shown in FIG. This increases the frictional resistance during rotation of 38.

In this embodiment, the fifth gear 40 is also concentrically and rotatably attached to a pin (not shown) implanted at the other end of the swinging member 36 . The diameter of the head of the pin is larger than the diameter of the main body, and a biasing means similar to the biasing means 48 described above is provided between the head of the pin and the lower surface of the fifth gear 40. It is located. The latter biasing means (not shown) increases the pressing force of the upper surface of the fifth gear 40 against the lower surface of the swinging member 36, thereby increasing the frictional resistance when the fifth gear 40 rotates. .

Suppose now that the bidirectional electric motor 34 rotates in one direction shown by arrow A in FIG. Then, the capstan 26 and the third gear 28 also rotate in one direction shown by arrow B. Frictional force between the third gear 28 and the fourth gear 38 and the third gear 28 and the fifth gear 40
Due to the frictional force between the swinging member 36 and the first
The fourth gear 3 rotates clockwise in the figure.
8 is meshed with the first gear 22. The position of the swinging member 36 at this time is defined as the first position of the swinging member 36. When the rocking member 36 is placed in the first position, the fifth gear 40 is spaced apart from the second gear 24, as shown in FIG. As the third gear 28 rotates in the direction of arrow B, the fourth gear 3
8 rotates in the direction shown by arrow C in FIG. 1, and the first gear 22 of the first reel shaft 10 rotates clockwise as shown by arrow D in FIG.

In this embodiment, bidirectional motor 34 is shown at arrow A
When rotating in one direction as shown by , a pinch roller (not shown) comes into contact with the magnetic recording tape 32 and cooperates with the capstan 26 to pinch the magnetic recording tape 32 . Further, the second reel shaft 12 is rotatable relative to a substrate (not shown). Therefore, the magnetic recording tape 32 is transferred to the second reel hub 1 by the action of the capstan 26 and a pinch roller (not shown).
After being pulled out from 8, it is wound onto the first reel hub 14. In this embodiment, the second reel shaft 12 is provided with a friction means for increasing the rotational frictional force against a substrate (not shown), such as a sliding contact fixed to the second reel shaft 12 and slidingly contacted with a substrate (not shown). It has a member. Due to the action of the friction member, the second reel hub 18 and the camp stan 26
Since back tension acts on the magnetic recording tape 32 between the capstan 26 and the second reel hub 18, the magnetic recording tape 32 will not loosen between the capstan 26 and the second reel hub 18.

The swinging member 36 has a friction force between the third gear 28 and the fourth gear 38 rotating in the direction of arrow B and a friction force between the third gear 28 and the fifth gear 40. The force exerts a biasing force toward the first position. Therefore, while the bidirectional electric motor 34 is rotating in the direction of arrow A, that is, while the capstan 26 is rotating in the direction of arrow B, the meshing between the fourth gear 38 and the first gear 22 is released. It will not be done. The force that urges the swinging member 36 to the first position is
An increase in the rotational frictional force by the biasing means 48 on the swinging member 36 of the fourth gear 38 as described above, and an increase in the rotational frictional force by the biasing means (not shown) on the swinging member 36 of the fifth gear 40 as described above. It has been increased by.

In this embodiment, a stopper portion 50 is formed at the other end of the swinging member 36 and extends in a clockwise direction in the circumferential direction. When the swinging member 36 is placed in the first position, the stopper portion 50 comes into contact with a stopper receiving portion 52 fixed to a substrate (not shown), as shown in FIG. Since the stopper portion 50 comes into contact with the stopper receiving portion 52, the pressing force of the fourth gear 38 on the first gear 22 does not become excessive, and the fourth gear 38 and the first gear 22 are Can fit smoothly.

Next, assume that the bidirectional motor 34 rotates in the other direction, which is the direction opposite to the direction indicated by arrow A in FIG. Then, the capstan 26 and the third gear 28
also rotates in the other direction, which is the opposite direction to the direction indicated by arrow B. Frictional force between the third gear 28 and the fourth gear 38 and the third gear 28 and the fifth gear 40
Due to the frictional force between them, the swinging member 36 rotates counterclockwise in FIG. 1, causing the fifth gear 40 to mesh with the second gear 24 as shown in FIG. The position of the swinging member 36 at this time is
6 second position. When the rocking member 36 is placed in the second position, the fourth gear 38 is spaced apart from the first gear 22, as shown in FIG. Third
As the gear 28 rotates in the direction opposite to the direction indicated by the arrow B, the fifth gear 40 rotates in the direction indicated by the arrow E in FIG. The gear 24 is indicated by arrow F in FIG.
Rotates counterclockwise as shown.

In this embodiment, bidirectional motor 34 is shown at arrow A
When the pinch roller (not shown) rotates in the other direction, which is the opposite direction to the direction indicated by
Separate from 2. Also, this time, the first reel shaft 1
0 is rotatable relative to a substrate (not shown). Therefore, the magnetic recording tape 32 is attached to the second reel shaft 12.
After being pulled out from the first reel hub 14 by the rotational force of the reel, it is wound onto the second reel hub 18. Note that in this embodiment, the first reel shaft 10
is a friction means for increasing the rotational friction force against the substrate (not shown), for example, the first reel shaft 10.
a sliding contact member that is fixed to and comes into sliding contact with a substrate (not shown);
have. Because back tension acts on the magnetic recording tape 32 between the second reel hub 18 and the first reel hub 14 due to the action of the friction member, the tension between the second reel hub 18 and the first reel hub 14 is reduced. There is no slack in the magnetic recording tape 32 and the magnetic recording tape 32 wound around the second reel hub 18.

The swinging member 36 has a friction force between the third gear 28 and the fourth gear 38 rotating in the direction opposite to the arrow B, and a friction force between the third gear 28 and the fifth gear 40. Due to the frictional force of , a force is applied that urges it to the second position. Therefore, while the bidirectional electric motor 34 is rotating in the direction opposite to the direction indicated by arrow A, that is, while the capstan 26 is rotating in the direction opposite to the direction indicated by arrow B, the fifth gear 40 and the fifth gear The meshing with the second gear 24 is never released. The force that urges the swinging member 36 to the second position is due to an increase in the rotational frictional force of the fourth gear 38 against the swinging member 36 due to the urging means 48 as described above, and an increase in the rotational friction force of the fifth gear 40 as described above. This is increased by increasing the rotational friction force applied to the swinging member 36 by a biasing means (not shown).

In this embodiment, a stopper portion 54 is formed at one end of the swinging member 36 and extends counterclockwise in the circumferential direction. The stopper portion 54 is
When the swinging member 36 is placed in the second position, the third
As shown in the figure, it comes into contact with a stopper receiving portion 56 fixed to a substrate (not shown). Since the stopper portion 54 comes into contact with the stopper receiving portion 56, the pressing force of the fifth gear 40 on the second gear 24 does not become excessive, and the fifth gear 40 and the second gear 24
The two can fit together smoothly.

The reel shaft drive changing device for a magnetic recording tape running device of this invention is used in a one-motor central capstan type magnetic recording tape running device equipped with a first reel shaft and a second reel shaft. a first gear provided on the first reel shaft and rotating together with the first reel shaft; a second gear provided on the second reel shaft rotating together with the second reel shaft; provided on the capstan and rotated together with the capstan. a rotating third gear; a fourth gear rotatably attached to one end and meshed with the third gear; a fifth gear rotatably attached to the other end and meshed with the third gear; has
The approximately intermediate portion is swingably attached to the capstan, and when the fourth gear meshes with the first gear, the fifth
a first position where the fourth gear is separated from the second gear; and a fifth position when the fourth gear is separated from the first gear.
The frictional force between the third gear and the fourth gear and the second position where the gear is engaged with the second gear correspond to the rotation of the capstan in one direction or the other direction. It is characterized by comprising: a swinging member that swings due to the frictional force between the third gear and the fifth gear.

With this configuration, the frictional force of the balls or rollers is not used, so changing between the drive of the magnetic recording tape by the first reel shaft and the drive by the second reel shaft is possible without oil or dust. This can be done reliably without being hindered by the intrusion of foreign substances. Furthermore, the structure can be simpler than that of the conventional one, thereby reducing the cost required for manufacturing and assembly.

The above-mentioned embodiments are for explaining this invention, and are not intended to limit this invention in any way.
It goes without saying that all modifications, modifications, etc. made within the technical scope of this invention are also included in this invention.

[Brief explanation of the drawing]

FIG. 1 is a plan view schematically showing the swinging member of the embodiment of the present invention in a first position, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIG. FIG. 3 is a plan view schematically showing a state in which the swinging member shown in FIG. 1 is placed in a second position. DESCRIPTION OF SYMBOLS 10... First reel shaft, 12... Second reel shaft, 14... First reel hub, 16... First reel hub attachment part, 18... Second reel hub, 20...
Second reel hub attachment part, 22...first gear, 2
4... Second gear, 26... Capstan, 28... Third gear, 30... Flywheel, 32... Magnetic recording tape, 33... Drive belt, 34... Bidirectional electric motor, 36... Swinging member, 38... Fourth gear, 40...
Fifth gear, 42...pin, 44...head, 46...main body, 48...biasing means, 50...stopper portion, 52...
Stopper receiving part, 54...stopper part, 56...stopper receiving part.

Claims (1)

[Claims for Utility Model Registration] In a one-motor central capstan type magnetic recording tape running device equipped with a first reel shaft and a second reel shaft, a first
a first gear provided on the reel shaft and rotating together with the first reel shaft; a second gear provided on the second reel shaft rotating together with the second reel shaft; provided on the capstan and rotating together with the capstan. a third gear; a fourth gear rotatably attached to one end and meshed with the third gear; and a fifth gear rotatably attached to the other end and meshed with the third gear. death,
The approximately intermediate portion is swingably attached to the capstan, and when the fourth gear meshes with the first gear, the fifth
a first position in which the fourth gear is separated from the second gear; and a fifth position in which the fourth gear is separated from the first gear.
The frictional force between the third gear and the fourth gear and the second position where the gear is engaged with the second gear correspond to the rotation of the capstan in one direction or the other direction. A reel shaft drive changing device for a magnetic recording tape running device, comprising: a swinging member that swings due to a frictional force between a third gear and a fifth gear.