JPH0432453B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape loading mechanism in a magnetic recording/reproducing device, and in particular to an operation switching mechanism for loading a tape into a cylinder and changing the tape running mode using one motor. Regarding the mechanism.

Conventionally, in magnetic recording and reproducing devices, the operation of pulling out a tape from a cassette and winding it around a cylinder at a predetermined angle, and the operation of changing the tape running mode (for example, playback, reverse playback, stationary playback, high-speed playback, etc.) are performed in one step. A mechanism using two motors is known.

One conventional example will be explained using FIGS. 1, 2, and 3. FIG. 1 is a plan view of the magnetic recording and reproducing apparatus before the tape is mounted on the cylinder, FIG. 2 is a plan view of the magnetic recording and reproducing apparatus after the tape is mounted on the cylinder, and FIG. It is an explanatory view of an operation switching mechanism. In FIG. 1, 1 is a chassis, 2 is a cassette half, and a supply reel 3 and a take-up reel 4 are housed in the cassette half 2, and a tape 5 is disposed between the reels 6a to 6f.
It is stretched by six guide pins. With the cassette half 2 installed, the capstan 7, the inlet tape guide group 8, the outlet tape guide group 9, and the tension pin 10 are inserted into the tape path formed by the guide pins 6a to 6f. .

On the other hand, on the chassis 1 are a rotary cylinder 11 equipped with a magnetic head (not shown), fixed guides 12a and 12b for securing the wrapping angle of the tape 5 around the tension pin 10, and a rotating cylinder 11 for erasing the entire width of the tape. Erase head 13, tape 5 for
an impedance roller 14 which damps longitudinal vibrations in the running direction of the tape by being rotationally driven at the same circumferential speed as the running speed of the tape; and a control for recording and reproducing signals that control the running speed and phase of the tape 5; Pinch rollers 16 are placed between the head 15 and the capstan 7 to drive the tape 5 by pinching and pressing the tape 5.

FIG. 2 shows a state in which the tape 5 is loaded. Here, the entry side guide group 8 and the exit side guide group 9 move along the paths indicated by broken line arrows A and B, respectively, and wind the tape 5 around the cylinder 11 at a predetermined angle without twisting. is held fixed in the desired position. Also, tension pin 1
0 rotates in the direction of the broken arrow C, detects the tension of the tape 5, and controls the load torque applied to the supply reel 3 in order to keep the tape tension constant at the position after rotation. On the other hand, the pinch roller 16 rotates in the direction of the dashed arrow D, presses against the capstan 7, and drives the tape 5.

In FIG. 3, 17 is a drive gear powered by a drive motor (not shown), 18 is an idle gear for transmitting power to the loading gear 19 on the input side, and 20 is the loading gear 19 on the input side and the output gear. An idle gear 22 is used to reverse the rotational direction of the side loading gear 21, and a reduction gear 22 is used to match the loading time on the entry and exit sides, which have different loading lengths. A pin 19a is implanted in the loading gear 19 on the entry side, and two arms 23 and 24 are inserted between it and a pin 8b implanted on the base 8a on which the entry guide group 8 is placed.
It is connected by A compression spring 25 is stretched between a locking hole 24a provided in the arm 23 and a pin 23a implanted on the arm 24.

The same goes for the exit side, a pin 21a is planted on the exit loading gear 21, and two arms are inserted between it and a pin 9b planted on the base 9a on which the exit side guide group is placed. They are connected by 26 and 27. A locking hole 27a provided in the arm 26 and a pin 26a implanted on the arm 27.
A compression spring 28 is stretched between the two.

On the other hand, 29 is a cam groove 29a for causing the pinch roller 16 to press against the capstan 7.
30, 31 and 32 are a connecting slider and a connecting lever for transmitting the displacement of the cam groove 29a to the pinch roller arm 33.

Drive gear 17 receives power from the drive motor.
rotates in the direction of arrow A, the entry loading gear 19 and the exit loading gear 21 rotate in the directions of arrows B and C, respectively, and accordingly, the entry guide group 8 and the exit loading gear connected to each loading gear rotate. The guide group 9 moves. After the entry side guide group 8 and the exit side guide group 9 have moved to predetermined positions, they are prevented from moving by a locking member (not shown), but the loading gears 19 and 21 on the entry side and the exit side are prevented from moving. In order to continue rotating further, the crimping springs 25 and 28 are stretched, and the spring force causes the entry guide group 8 and the exit guide group 9 to be strongly pressed against the locking member and fixed and held in a predetermined position. Become.

On the other hand, when the drive gear 17 rotates in the direction of arrow A, the cam gear 29 simultaneously rotates in the direction of arrow D, and as the cam groove 29a rotates, the radial position of the groove is displaced. This displacement is transmitted to the pinch roller arm 33 via the connecting slider 30 and the connecting levers 31 and 32, whereby the pinch roller 16 is rotated and pressed against the capstan 7. Here, the phase is adjusted so that the pressing operation of the pinch roller 16 is performed until the pressing operation of the guide groups 8 and 9 on the entry side and the exit side is completed.

In this mechanism, when changing the running mode of the tape 5 from normal playback to still image playback or high-speed playback, or when rewinding or fast forwarding the tape 5 while it is still mounted on the cylinder 11, ,
It is necessary to perform operations such as separating the pinch roller 16 that is in pressure contact from the capstan 7 and changing the load applied to the reels 3 and 4 in order to apply appropriate tension to the running tape. To perform these operations, there is a method of using a solenoid, but in order to make the magnetic recording and reproducing device smaller and lighter, it is more advantageous to drive each member by displacement of a cam groove provided in the cam gear 29. It is. Although only the cam groove 29a for rotationally driving the pinch roller 16 is shown in FIG. 3, in order to operate other members,
The cam gear 29 may be provided with a plurality of grooves corresponding to each operation. However, in this case, in order to run the tape 5 stably without twisting, it is necessary to keep the guide groups 8 and 9 pressed against the locking members. Therefore, the cam gear 29 is
It will rotate further in the direction of . As a result, the inlet loading gear 19 and the outlet loading gear 21 also rotate in the directions of arrows B and C, respectively, and the crimping springs 25 and 28 of the guide groups 8 and 9 are stretched more than necessary, and the drive motor is It takes a load. Furthermore, while the guide groups 8 and 9 move from the position housed in the cassette half 2 as shown in FIG. 1 to the position shown in FIG. 2, the cam gear 29 is also rotationally driven at the same time. The cam groove provided in the gear 29 requires a relief portion corresponding to this period, and there is a problem that the cam gear itself becomes large.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, to efficiently perform the operations of loading a tape onto a cylinder and changing the running mode of the tape with a single motor, thereby contributing to miniaturization of magnetic recording and reproducing devices. The goal is to provide a mechanism that can contribute.

In order to achieve the above object, the present invention provides (a) a loading drive member (corresponding embodiment code 19, 21) for wrapping tape around the outer periphery of the cylinder;
and a mode operating member for changing the running mode of the tape (corresponding embodiment codes 30, 31, 32,
33) and a differential transmission mechanism that switches the transmission path to the side with the smaller load torque and selectively transmits the output from one drive source to the loading drive member or the mode operation member (corresponding embodiment numerals 35 and 36) , 37) and first and second stopper mechanisms for respectively stopping the loading drive member and the mode operating member at predetermined positions, (b) the loading drive member is connected to the differential transmission; (c) connected to one output rotation part side of the mechanism and positioned and held by the first stopper mechanism at least at a first position where loading is started and a second position where loading is completed; The mode operating member is connected to the other output rotating portion side of the differential transmission mechanism via a rotary cam member (corresponding embodiment code 29); The loading drive is configured such that the stopper members (numbers 38 and 39 in the corresponding embodiment) prevent movement in the unloading direction at the first position and from movement in the loading direction at the second position. First holding portions at multiple locations on the member in the moving direction (corresponding example code 19b,
19c), and when the holding is released, the moving force of the loading drive member itself causes the first
(e) The second stopper mechanism is configured such that the second stopper member (reference numeral 40 in the corresponding embodiment) is disengaged from the second stopper member on the rotary cam member. It is configured to be engaged with the holding part (corresponding embodiment code 29b), and when the holding is released, the engaged state in the second holding part is released by the rotational movement force of the rotary cam member itself, ( f) When the loading drive member makes a loading movement and an unloading movement, the first stopper mechanism receives the load torque from the second stopper mechanism and the rotary cam member through the loading drive member. The differential transmission mechanism is configured to apply a small load torque to the differential transmission mechanism even when the mode operation member is operated, and to apply the same large load torque when the mode operation member moves.

An embodiment of the present invention will be described with reference to FIGS. 4 and 5. Here, parts common to those in FIGS. 1, 2, and 3 are given the same numbers.

FIG. 4 is a plan view showing an operation switching mechanism using a differential gear train, and FIG. 5 is an explanatory view showing the three-dimensional structure of the mechanism. Both figures show a state in which the tape is mounted on the cylinder and the pinch roller is pressed against the capstan.

In FIGS. 4 and 5, 34 is a drive gear to which power is transmitted from a motor (not shown), 35 has internal teeth 35a and external teeth 35b;
A transmission gear rotating around the same central axis as 3
6 is the internal tooth 35a of the drive gear 34 and the transmission gear 35.
A gear 37 that meshes with the gear 37 is a gear that is coupled to the rotation center axis of the gear 36 and rotates around the same center axis as the drive gear 34 as the gear 36 revolves around the drive gear 34 . On the other hand, 38 is a stopper mechanism for instantaneously changing the rotational load on the loading gear side, with 38a as the spindle, and a roller 38d rotatably attached to a pin 38c implanted at one end of the arm 38b. Stopper groove 19
Inlet loading gear 19 with b and 19c
It is rotationally biased by a spring 38e so that it is always pressed against the outer peripheral cylindrical portion 19d. 39 also 3
This is a stopper mechanism similar to No. 8, and the explanation thereof will be omitted. Further, 40 is a stopper mechanism for instantaneously changing the load on the cam gear side, and a roller 40d is rotatably attached to a pin 40c implanted at one end of an arm 40b, with 40a as a pivot. The cam gear 29 is rotationally biased by a spring 40e so as to be constantly pressed against the outer cylindrical portion 29c of the cam gear 29 provided with the stopper groove 29d.

As shown in FIG. 1, when the guide groups 8 and 9 are housed in the cassette half 2, the roller 38d of the stopper 38 is inserted into the stopper groove 19c of the entry side loading gear 19, and the cam gear 29 Similarly, the roller 40d of the stopper 40 is inserted into the stopper groove 29b.

At this time, stopper 3 on the entry side loading gear side
8, the position of the support shaft 38a and the tension of the spring 38e are adjusted so that it can easily come out of the stopper groove 19c against the rotational driving force in the direction of arrow B, and never come out and bite against the rotational driving force in the opposite direction. On the other hand, the stopper 40 on the cam gear side is configured so that it can escape from the stopper groove 29b in response to rotational driving force in either the direction of arrow D or the opposite direction in order to perform an auto-eject operation of the cassette box to be described later. Select the position of the support shaft 40a, and set the tension of the spring 40e so that the rotational load of the entire cam gear 29, including the load caused by the stopper locking, is greater than the rotational load of the entire loading gear side in terms of the rotational axis of the drive gear 34. Set.

Here, when the drive gear 34 is rotated in the direction of arrow A, the loading gear side with less rotational load is rotationally driven, and the cam gear side is maintained in a stopped state. In this case, since the internal gear 35a is fixed, the gear 3
6 becomes a planetary gear and revolves around the sun gear 34, which drives the gear 37 to rotate, and the gear 1
8, 20 and 22, the inlet loading gear 19 and the outlet loading gear are connected to the arrow B, respectively.
and C directions, and the guide groups 8 and 9 move accordingly. Here, guide groups 8 and 9
is locked in a predetermined position by a locking member (not shown), and the crimping springs 25 and 28 are stretched to generate a predetermined crimping force, when the stopper 3
The stopper groove 1 is inserted so that the roller 39d of No. 9 enters the stopper groove 19b of the entry side loading gear 19.
On the other hand, the stopper 39 is designed to prevent the roller 39d from coming out of the stopper groove 19b against the rotational driving force in the direction of arrow B, and to prevent the roller 39d from coming out of the stopper groove 19b against the rotational driving force in the opposite direction. The position of the support shaft 39c and the tension of the spring 39e are set so that it does not slip out of the stopper groove 19b due to the load on the cam gear side during such operations.

Stopper groove 19b of entry side loading gear 19
As the roller 39d of the stopper 39 enters the rotation of the loading gear side, the gear 36 stops its revolving operation and starts transmitting rotational driving force to the gear 35 as an idle gear.
The roller 40d of the stopper 40 comes out of the stopper groove 29b of the cam gear 29, and the cam gear 29 is driven to rotate in the direction of arrow D. And cam gear 29
As the cam groove 29a rotates, the cam groove 29a is displaced, whereby the pinch roller 16 is pressed against the capstan 7. Although FIG. 4 only shows the cam groove 29a for the press-contact operation of the pinch roller 16, as described in the conventional example, the operations of other members necessary for changing the tape running mode and the running mode are necessary. In order to perform a slide switch operation or the like for detecting the conversion of the cam gear 29, the cam gear 29 may be provided with a plurality of cam grooves corresponding to each operation.

In order to store the tape loaded in the cylinder into the cassette half again, the drive gear 34 is driven to rotate in the opposite direction of arrow A. As a result, the cam gear 29 first rotates in the direction opposite to the arrow D, and the roller 40d of the stopper 40 enters the stopper groove 29b. In this state, the roller 39d of the stopper 39 is inserted into the stopper groove 19b of the entry side loading gear 19, but the rotational load of the entire cam gear 29 including the stopper locking is applied to the drive gear 34.
If the tension of the spring 40e is set so that it is larger than the entire rotational load on the loading gear side in terms of the rotational axis, the stopper 39 on the loading gear side, which has less rotational load, will pop out of the stopper groove and be released from the lock. , the inlet loading gear 19 and the outlet loading gear 21 are driven to rotate in the directions opposite to the arrows B and C, respectively, and the guide groups 8 and 9 move toward the cassette half. And the stopper groove 19 of the entry side loading gear 19
The series of operations is completed by the roller 38d of the stopper 38 entering again at point c.

Here, in order to perform an auto-eject operation of the cassette box, the drive gear 34 is further rotated in the direction opposite to arrow A to release the cam gear 29 from the stopper 40, and the cam gear 29 is released. Rotate in the direction opposite to arrow D. The cam gear 29 is provided with a cam groove for auto-eject operation, and the displacement of this cam groove drives the member to perform the auto-eject operation.

In the above example, both stopper mechanisms for instantaneously changing the rotational load are provided on the inlet loading gear, but it is also possible to provide one or both on the outlet loading gear.

Furthermore, in the above embodiment, when transmitting the driving force to the loading gear side, the gears 34, 35 and 37
The configuration is such that it becomes a differential gear train, but
It is also possible to configure this so that it becomes a differential gear train when transmitting driving force to the cam gear side.

Further, in the above example, the gear 34 is connected to the motor and driven, and the gear 35 and the gear 37 are used as driven gears to drive the loading gear train and the cam gear train, respectively, but the gear 35 is connected to the motor. It is also possible to adopt a configuration in which the gears 34 and 37 are driven as driven gears, or a configuration in which the gear 37 is connected to a motor and the gears 34 and 35 are driven as driven gears.

It is also possible to use a friction wheel instead of a gear.

According to the present invention described above, since the tape loading operation on the cylinder and the tape running mode conversion operation can be performed efficiently and completely separated by one motor, the cam involved in the running mode conversion operation can be performed efficiently. The gear can be made smaller, which greatly contributes to the miniaturization of the magnetic recording/reproducing device itself, and at the same time, unnecessary motor load can be removed, thereby reducing power consumption. Further, there is no need for a switch for detecting the completion of the tape mounting operation on the cylinder and the tape storage operation on the cassette half, and the adjustment work for installing this switch can be eliminated, resulting in cost reduction.

[Brief explanation of drawings]

Fig. 1 is a plan view of the magnetic recording/reproducing device before the tape is mounted on the cylinder, Fig. 2 is a plan view of the magnetic recording/reproducing device after the tape is mounted on the cylinder, and Fig. 3 shows the operation switching of the conventional example. FIG. 4 is a plan view showing an operation switching mechanism using a differential gear train according to the present invention, and FIG. 5 is an explanatory view showing the three-dimensional structure of the mechanism. 8...Inlet guide group, 9...Outlet guide group, 16...
Pinch roller, 19... Entrance side loading gear, 2
1... Output side loading gear, 29... Cam gear, 3
4... Drive gear, 38, 39 and 40... Stopper mechanism.

Claims (1)

[Claims] 1. A loading drive member that winds the tape around the outer circumference of a cylinder, a mode operating member that changes the running mode of the tape, and a drive source that switches the transmission path to the side with the smaller load torque. a differential transmission mechanism that selectively transmits an output to the loading drive member or the mode operation member, and first and second stopper mechanisms that stop the loading drive member and the mode operation member at predetermined positions, respectively. In the magnetic recording and reproducing device, the loading drive member is connected to one output rotating section side of the differential transmission mechanism, and has at least a first position where loading is started and a second position where loading is completed. is positioned and held by the first stopper mechanism, the mode operating member is connected to the other output rotating section side of the differential transmission mechanism via a rotary cam member, and the first stopper mechanism is , the first stopper member prevents movement in the unloading direction at the first position and movement in the loading direction at the second position, respectively. The second stopper mechanism is configured to be engaged with a first holding portion at a location, and to be disengaged from the first holding portion by the moving force of the loading drive member itself when the loading drive member is released from the holding portion. The second stopper member is engaged with the second holding portion on the rotary cam member, and when the holding is released, the second stopper member is engaged with the second holding portion by the rotational movement force of the rotary cam member itself. The first stopper mechanism is configured to disengage the second stopper mechanism via the loading drive member when the loading drive member makes a loading movement and when the loading drive member makes an unloading movement. A load torque smaller than the load torque by the mechanism and the rotary cam member is applied to the differential transmission mechanism, while the same larger load torque is applied when the mode operation member moves. magnetic recording and reproducing device.