JPH043018B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a main side gear that can rotate multiple times, and a slave side that rotates intermittently and within a range of less than one rotation in response to the rotation of the main side gear. The present invention relates to a drive device having a gear.

[Background of the invention]

Various types of drive devices have been proposed that have a plurality of gears, and each gear has a time lag in rotation to perform a plurality of drive operations.

For example, in the case of magnetic recording and reproducing devices such as VTRs,
Conventionally, a first gear having a surface cam on its upper surface, a first motor for rotating the first gear, and a first gear are provided.
a second gear having surface cams on its upper and lower surfaces, a second motor and second speed reducer that rotate the second gear, and a pin that engages with the surface cam of the first gear. A lever for attaching a cassette,
A drive including a lever for moving the pinch roller with a pin that engages with a surface cam on the upper surface of the second gear, and a lever for pulling out the tape that has a pin that engages with the surface cam on the lower surface of the second gear. There is a device. This drive device drives the first and second motors with a predetermined time lag, and transmits the rotational force of these motors to the first and second gears via the first and second reduction gears. This drives the cassette loading lever, pinch roller moving lever, and tape pull-out lever at predetermined timing, and controls the loading of the cassette, the ejecting operation, the moving operation of the pinch roller, and the drum cylinder for the tape in the cassette. The tape is wound onto the cassette, and the tape is returned into the cassette. However, in the drive device configured in this way, the first and second motors and the first and second reduction gears, that is, two gears, correspond to the first gear and the second gear, respectively. This requires a driving source, resulting in high manufacturing costs, and also has the disadvantage of not being able to save space.

[Purpose of the invention]

The present invention has been made in view of the actual situation in the prior art, and an object thereof is to provide a drive device having gears that can reduce the number of drive sources.

[Summary of the invention]

To achieve this objective, the present invention includes a main gear mounted on a first shaft and capable of multiple rotations, and a main gear mounted on a second shaft capable of engaging and disengaging from the main gear. a subordinate gear; a force applying means for applying a force to the subordinate gear to engage the main gear and the subordinate gear; and engagement between the main gear and the subordinate gear in conjunction with rotation of the main gear; and disengagement means for disengaging the first shaft and the second shaft, and means for disabling the action of the disengagement means when the main side gear rotates by a certain angle. It has a well-equipped structure.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A drive device having gears according to the present invention will be described below with reference to the drawings. FIGS. 1 and 2 are explanatory diagrams showing essential parts of an embodiment of the present invention, and FIG. 1 is a plan view;
FIG. 2 is a side view. Note that this example
An example of application to a VTR drive section is shown. In these figures, 1 is the motor, 2 is this motor 1
3 is a belt that transmits the rotational force of the motor 1 to the pulley 2; 4 is a worm that rotates integrally with the pulley 2; 5 is a worm wheel that engages with the worm 4; 6 is the worm wheel 5. It is a gear formed at the bottom of the .

The above-mentioned worm wheel 5 and gear 6 are integrated to form a main gear, and as shown in FIG. 2, the worm wheel 5 and the gear 6 are mounted on a first shaft 8 fixed to the chassis 7 so as to be able to make multiple rotations, for example, two rotations. There is. Further, the worm wheel 5 has a surface cam 10 forming a recessed portion on its surface 9 as shown in FIG.
0 is an approximately two-turn winding having a portion 13 that gradually approaches the center from position 11 to position 12, and a portion 14 that is continuous with this portion 13 at position 12 and is approximately equal in distance from the center. It is formed in a spiral shape. In addition, the gear 6 mentioned above
The surface 18 located below in FIG. 2 of FIG.
As shown in c, another surface cam 19 is formed, and this surface cam 19 is provided at a position far from the center, and has a portion 20 that is approximately equal in distance from the center.
, a portion 21 provided at a position close to the center and having approximately the same distance from the center, and these portions 20
and a portion 22 connecting the portions 21 and 21, and is formed in an approximately two-turn spiral shape. A gear portion 23 and a non-gear portion 24 corresponding to the addendum circle are formed on the circumferential side of the gear 6.

Reference numeral 15 shown in FIG. 1 is a cassette mounting lever, which is rotatably mounted on a shaft 16 fixed to the chassis 7 and includes a pin 17 that engages with the surface cam 10 of the worm wheel 5 described above. . Reference numeral 25 denotes a subordinate gear that can be engaged with and disengaged from the gear 6, and is rotatably mounted on a second shaft 26 fixed to the chassis 7 within a range of less than one rotation. A surface cam (not shown) is formed on the upper and lower surfaces of the subordinate gear 25, and on the circumferential side thereof, a gear portion 27 and a non-gear portion corresponding to the root circle are formed as shown in FIGS. Part 28
is formed. Reference numeral 29 denotes a pinch roller moving lever, which has a pin 30 that engages with a surface cam (not shown) formed on the upper surface of the follower gear 25, and is rotatably mounted on a shaft 31 fixed to the chassis 7. There is. Reference numeral 32 denotes a tape drawer lever, which has a pin 33 that engages with a surface cam (not shown) formed on the lower surface of the slave gear 25, and which is attached to a shaft 3 fixed to the chassis 7.
It is rotatably attached to 4. Note that a boss 35 that projects downward is formed on the lower surface of the slave gear 25.

36 is a first lever; 37 is a second lever that engages with this first lever 36;
6 has a pin 38 at one end that engages with a surface cam 19 formed on the gear 6 constituting the main side gear, and has an elongated hole 39 at the other end, and is rotatable around a shaft 40 fixed to the chassis 7. The second lever 37 has a pin 41 that engages with the elongated hole 39 of the first lever 36, and has a protrusion 42 on the side that can engage with the aforementioned boss 35, Chassis 7
It is rotatably mounted on a shaft 43 fixed to the.
The first lever 36 and the second lever 3 described above
Reference numeral 7 constitutes an engagement release means for disengaging the gear 6 and the slave gear 25 in conjunction with the rotation of the gear 6 constituting the main gear.

Further, a spring 44 is held by the shaft 43, has one end engaged with the second lever 37, and extends in the direction of the slave gear 25 so that the other end can contact the boss 35 of the slave gear 25. This spring 44 is a means capable of biasing the subordinate gear 25 to rotate in the direction of arrow 45 in FIG. This constitutes force applying means for applying force to the subordinate gear 25.

The operation of the embodiment configured in this way is as follows.

That is, in the eject state before the cassette is installed at a predetermined installation position, the pin 17 of the cassette installation lever 15 is at position 1 of the portion 13 of the surface cam 10 of the worm wheel 5 shown in FIG.
It is in 1. Further, the gear 6 constituting the main gear and the slave gear 25 have a positional relationship as shown in FIG. 4a.
At this time, the first
The pin 38 of the second lever 36 is engaged, the protrusion 42 of the second lever 37 is in contact with the boss 35 of the slave gear 25, and the spring 44 is in contact with the boss 35. That is, the boss 35 is held between the protrusion 42 of the second lever 37 and the spring 44.

From this ejected state, the motor 1 shown in Figure 1
When the motor 1 is driven, the rotational force of the motor 1 is applied to the belt 3.
is transmitted to the pulley 2, worm 4, or worm wheel 5 via the worm wheel 5.
As the gear 6 rotates, the gear 6 constituting the main side gear shifts to the fourth gear.
Rotate in the direction of arrow 47 in figure a. When the gear 6 rotates approximately once in this manner, the pin 17 of the cassette mounting lever 15 moves from the position of the surface cam 10 of the worm wheel 5 to the position 12 via the portion 13.
Therefore, the cassette mounting lever 1 shown in FIG.
5 rotates around a shaft 16 to place a cassette (not shown) at a predetermined mounting position, and this cassette mounting operation is completed.

Also, while the gear 6 rotates approximately once in this way,
The pin 38 of the first lever 36 passes through the part 20 of the surface cam 19 and reaches the part 22, but the pin 38 and the part 2
The first lever 36 does not rotate while the boss 3 is engaged with the boss 3 as shown in FIG. 4a.
5 is held between the protrusion 42 of the second lever 37 and the spring 44, the slave gear 25 does not rotate, and as the pin 38 engages the portion 22, the first lever 36 is centered on the axis 40 in Fig. 4a.
Rotate in the direction of arrow 48, and remove the elongated hole 39 and pin 4.
1 , the second lever 37 rotates about the shaft 43 in the direction of arrow 49 , whereby the protrusion 42 of the second lever 37 engages with the boss 35 of the slave gear 25 .
The force of the spring 44 urges the slave gear 25 in the direction of the arrow 50 in FIG. 4a, resulting in the state shown in FIG. 4b.

Further, when the motor 1 is driven from the state shown in FIG.
In response to the rotation of the gear 6 that is less than one rotation, the slave gear 25 rotates less than one rotation in the direction of arrow 45 in FIG. 4b, and as shown in FIG. 4c. The state shown is reached. During this time, the slave gear 25
Pin 3 that engages with surface cams (not shown) on the upper and lower surfaces of
0 and 33 move, and the pinch roller moving lever 2
9 rotates, a pinch roller (not shown) moves,
The pinch roller pinches the tape in the cassette and presses it against the capstan, and the tape pull-out lever 32 rotates to pull out the tape in the cassette, and a loading operation is performed in which the tape is wound around a drum cylinder (not shown). . In this way, from the state shown in Fig. 4b to Fig. 4c
During the transition to the state shown in FIG.
Since the pin 17 engages with the portion 14 of the surface cam 10 of the worm wheel 5 shown in FIG. 3, no rotation occurs and the cassette is kept in a stable mounting state.

In this manner, the cassette loading operation, the pinch roller moving operation, and the tape drawing operation are performed.

Furthermore, in order to eject the cassette from the state shown in FIG. 4c, the motor 1 shown in FIG. 1 may be rotated in the opposite direction to that described above. This motor 1
As the gear 6 rotates, the gear 6 shown in FIG.
The slave gear 25 rotates in the direction of the arrow 54, and as the slave gear 25 rotates, the pinch roller moving lever 29 and the tape pull-out lever 32 rotate, and the pinch roller is removed from the capstan. The tape is moved away and the tape is pulled back into the cassette. During this time, the worm wheel 5 also rotates together with the gear 6 in the direction of arrow 55 in FIG. 3, and although the cassette mounting lever 15 does not rotate, the pin 17 reaches the position 12 of the surface cam 10.

When the motor 1 further rotates, the gear 6 rotates in the direction of the arrow 56 in FIG. During this time, as the pin 38 moves, the first lever 36 rotates in the direction of arrow 57 about the shaft 40, and as the first lever 36 rotates, the second lever 37 rotates in the direction of arrow 58. The protruding portion 42 contacts the boss 35 of the subordinate gear 25. Therefore, when the gear 6 rotates after the pin 38 has engaged with the portion 21 of the surface cam 19, the slave gear 25 remains stationary, and finally reaches the state shown in FIG. 4a. . Also during this time,
The worm wheel 5 rotates together with the rotation of the gear 6, but the pin 17 of the cassette mounting lever 15 moves from position 12 to position 11 shown in FIG. 3, so that the cassette mounting lever 15 rotates. , an eject operation is performed.

In the embodiment configured in this way, 1
The cassette device lever 15, the pinch roller moving lever 29, and the tape pull-out lever 32 can be driven by only one motor 1, and the number of drive sources can be minimized.

In addition, in this embodiment, since a non-gear portion 24 corresponding to the addendum circle is provided in a part of the tooth portion 6, the engagement between the tooth portion 51 and the tooth portion 52 shown in FIG. In this case, manufacturing errors between the pin 38 and the surface cam 19, such as looseness or
The influence of manufacturing errors of the lever 37 is absorbed, and the teeth 51 and 52 can be reliably engaged with each other.

In the above embodiment, the non-gear portion 24 corresponding to the tip circle is provided in a part of the tooth portion 6 as described above, but the manufacturing dimensions between the pin 38 and the surface cam 19,
If the manufacturing dimensions of the first lever 36 and the second lever 37 can be set with high precision, such a non-geared part 24 is not provided, and the entire circumference of the toothed part 6 is constituted by a geared part. be able to.

Furthermore, in the above embodiment, the slave gear 25 is provided with the non-gear portion 28 corresponding to the tooth root circle, but the present invention is not limited to this, and the non-gear portion 28 is provided further toward the center than the tooth root circle. It can also be configured by a cutout.

Further, in the above embodiment, one slave gear 25 is provided for the gear 6 constituting the main gear.
The present invention is not limited to this, and a plurality of subordinate gears 25 may be provided for one gear 6.

Further, in the above embodiment, the slave gear 25 is set to rotate less than one revolution while the main gear rotates approximately two times, but the present invention is not limited to this. If the device is a different device and another lever corresponding to the cassette mounting lever 15 is configured to rotate while the slave gear 25 is rotating, the slave gear 25 may rotate while the main gear rotates three or more times. It is also possible to configure the side gear 25 to rotate within a range of less than one rotation.

Further, in the above embodiment, the worm wheel 5 and the gear 6, which constitute the main side gear, are provided with the surface cam 10 and the surface cam 19, however, the present invention is not limited to providing such surface cams 10 and 19. Instead of these surface cams 10 and 19, a worm wheel 5,
It is also possible to provide a cam, pin, etc. that protrudes from the surface of the gear 6.

Further, in the above embodiment, the force for engaging the gear 6 constituting the main gear and the subordinate gear 25 is applied to the subordinate gear 25.
5, a second lever 37 serves as a means for applying force to the
A spring 44 attached to a shaft 43 that forms the center of rotation of the
However, the present invention is not limited to this, and for example, a torsion spring may be attached to the second shaft 26 that forms the rotation center of the subordinate gear 25 so as to be able to come into contact with the boss 35. Instead of providing this, a cam mechanism or the like may be provided, and this cam mechanism may bias the slave gear 25 in the direction of arrow 50 in FIG. 4a as necessary.

〔Effect of the invention〕

Since the drive device having gears of the present invention is configured as described above, the number of drive sources can be reduced compared to the conventional one when performing multiple drive operations, and therefore manufacturing costs can be reduced. This has the effect of realizing space savings.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams showing essential parts of an embodiment of a drive device having gears according to the present invention, in which FIG. 1 is a plan view, FIG. 2 is a side view, and FIG. A plan view showing a worm wheel provided in the drive device shown in FIG. 2, and FIGS. 4a to 4c are explanations showing the operational relationship between the main gear and the slave gear in the drive device shown in FIGS. It is a diagram. 1...Motor, 2...Pulley, 3...Belt,
4...Worm, 5...Worm wheel, 6...
... Gear, 8 ... First shaft, 10, 19 ... Surface cam, 15 ... Cassette mounting lever, 17, 3
8, 41... Pin, 23, 27... Gear part, 2
4, 28... Non-gear part, 25... Follower gear, 26
... Second shaft, 29 ... Lever for moving the pinch roller, 32 ... Lever for drawing out the tape, 35 ... Boss, 36 ... First lever, 37 ... Second lever, 39 ... Elongated hole , 42... protrusion, 44... spring.

Claims (1)

[Claims] 1 A main gear mounted on a first shaft and capable of multiple rotations, a slave gear mounted on a second shaft and capable of engaging and disengaging from the main gear, and the main gear and a force applying means for applying a force to the slave gear to cause the slave gear to engage with the slave gear; and an engagement release means for disengaging the master gear and the slave gear in conjunction with the rotation of the master gear. and a means for setting a constant distance between the first shaft and the second shaft, and disabling the action of the disengagement means when the main side gear rotates by a certain angle. A drive device with gears.