JPH0433564Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to a mechanism for opening and closing an operating switch of a song interval detection circuit that detects fast-forwarding between songs or data in a magnetic recording/reproducing device such as a tape recorder.

<Conventional technology> Conventionally, mode switching was performed using the rotational force of a cam gear.
There is a mode switching mechanism for tape recorders, etc. called RAD (Power Assist Device). This was filed by the applicant in Japanese Patent Application No. 55-51071 (Japanese Unexamined Patent Publication No. 59-59
148754) as a mode switching device for tape recorders, etc.

In such a mode switching device, when the fast forward lever is pressed in the playback mode state, the track interval detection circuit is activated, the fast forward lever is locked by the plunger, and the magnetic head etc. are slightly lowered and the magnetic tape is pressed. The system is configured so that the running speed changes from a constant speed to a high-speed fast-forward state, and the detection between songs starts.

However, in such a mechanism, when the playback operation lever and the fast-forward operation lever are pressed simultaneously from a stopped state, the drive source such as a motor has a torque that drives the cam gear that moves the magnetic head etc. to the playback mode position. A high-torque drive source is required because the drive torque that activates the fast-forward mechanism and causes the magnetic tape to run at high speed is simultaneously applied. In addition, when transmitting driving force using a belt, etc., there is a possibility that the transmission force will weaken over time, and if the transmitted torque is smaller than necessary, There is a possibility that it will stop. Moreover, since the fast-forwarding lever is locked by the plunger, it is impossible to escape from this state except by releasing it with the stop operation lever.

<Purpose of the invention> The purpose of the invention is to prevent the song interval detection circuit from operating when the drive torque is insufficient, such as when the playback operation lever and the fast-forward operation lever are pressed simultaneously from a stopped state, thereby solving the above-mentioned drawbacks. The goal is to eliminate the

<Structure of the invention> In order to achieve the above-mentioned object, the invention switches modes by moving a magnetic head, etc. to a predetermined position by the rotational force of a cam gear having a drive cam on the same axis. Timing setting means having a mode switching mechanism and a song interval detection circuit, a timing cam provided coaxially with the cam gear, and following the timing cam to set the operation timing of the operating switch of the song interval detection circuit. After the magnetic head and the like move to the predetermined position, the actuating switch is set to an operable state by a timing setting means driven by the timing cam.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view of essential parts of an embodiment of the present invention, and this figure shows the stop mode. In the switch opening/closing operation mechanism of this embodiment,
A mode switching mechanism is provided for moving a magnetic head (not shown), a pinch roller lever 10, etc. to predetermined positions by the rotational force of a cam gear 2 having a drive cam 2c coaxially therewith. This mode switching mechanism includes a drive lever 7 driven by the drive cam 2c, a head plate 8, and a spring (not shown) that rotates the pinch roller lever 10 in a direction to press the capstan shaft 11 as the head plate 8 moves. Consists of means of transmission.

A timing cam 2b is integrally provided on the cam gear 2 on its coaxial center, and is further latched to the tip 4a of the trigger lever 4 at the stop mode position, playback mode position, and song interval detection mode position. It has locking pieces 2a, 2d, and 2e, and has a toothless portion on its outer periphery.

In the present invention, a timing setting means is provided which follows the timing cam 2b and sets the operation timing of the solenoid switch 26 as an operation switch of the inter-musical detection circuit (not shown), that is, the operable timing as described below. This timing setting means includes a timing lever 5, a standby lever 9, a switch lever 16, a blocking lever 6, etc., which will be described later.

The drive gear 3 is driven clockwise (direction of arrow E) in the figure by a motor or the like, and in the stop mode, playback mode, and song interval detection mode, the drive gear 3 faces the toothless portion of the cam gear 2 and When meshing with the toothed portion of the gear 2, power is transmitted to the gear 2.

The timing lever 5 engages with the timing cam 2b at its tip 5a, and is further urged clockwise in the figure by a trigger spring 25. The head plate 8 has a magnetic head (not shown) thereon, and guide pins 1j and 1k are inserted into guide grooves 8d and 8e so as to be movable in the directions of arrows C and D. Along with this movement of the head plate 8, the pinch roller lever 10 is rotated by a transmission means such as a spring (not shown) in a direction in which it is pressed against the capstan shaft 11 rotating at a constant speed, and the reel stand drive mechanism (not shown) is also activated. . That is, by sandwiching the magnetic tape between the pinch roller lever 10 and the capstan shaft 11, the tape is sent out at a constant speed and taken up on the take-up reel. When the drive lever 7 contacts the drive cam 2c at its one end 7b and the cam gear 2 rotates,
As the cam radius increases, the other end 7a displaces the head plate 8 in the direction of arrow C against the urging force of the return spring 17 via the overstroke spring 24 on the head plate 8. That is, the magnetic head etc. on the head plate 8 are moved to a predetermined mode position via this drive lever 7 which is driven by the drive cam 2c. Note that the overstroke spring 24 is wound around the shaft 8a on the head plate, and is locked with the locking shafts 8b and 8c in a state where energy is accumulated, so that no unnecessary force is applied to the head plate 8. It has the function of absorbing pressure.

The standby lever 9 is rotatable about a pivot shaft 1d, and is locked by a locking shaft 9a on the standby lever 9 and a locking portion 5b of the timing lever 5 in the stop mode. This standby lever 9 is activated by the connection spring 18 when the head plate 8 starts moving in the direction of arrow C as the cam gear 2 rotates counterclockwise as described below.
Although it is urged to rotate in the direction of arrow F, the rotation is prevented because the locking portion 5b and the locking shaft 9a are locked.

The blocking lever 6 has guide pins 1h and 1i inserted into guide grooves 6b and 6c, and is movable back and forth in the directions of arrows C and D, and is biased in the direction of arrow D by a return spring 19. There is. Playback control lever 1
3 has guide pins 1l and 1m inserted into guide grooves 13b and 13c thereon, so that it can be reciprocated in the directions of arrows C and D, and is biased in the direction of arrow D by a return spring 21. Similarly, the stop lever 14 also has guide pins 1n, 1 in the guide grooves 14b, 14c.
o is inserted, and is urged in the direction of arrow D by the return spring 22.

The lock plate 12 has guide pins 1p and 1q inserted into guide grooves 12c and 12d, is movable back and forth in the directions of arrows A and B, and is biased in the direction of arrow A by a return spring 20. The regeneration operation lever 13 has an engaging portion 13a, and the stop lever 14 has a lock release portion 14a. By operating the regeneration operation lever 13, the engaging portion 13a engages the lock piece 12 of the lock plate 12.
When the lock plate 12 is moved in the direction of arrow B against the biasing force of the return spring 20 and moved to the operating position, the lock plate 12 is pressed against the return spring 20.
It returns to the direction of arrow A and is locked. In the lock release cam 12b, the lock release portion 14a moves the lock plate 12 in the direction of arrow B when the stop lever 14 is operated. As a result, the playback operation lever 1
3 and the lock piece 12 of the lock plate 12
The lock with a is released.

The trigger lever 4 is rotatably supported by a pivot shaft 1b, and an interlocking pin 13d on the regeneration operation lever 13 is inserted into the engagement groove 4b to be operated in an interlocking manner. Further, the tip portion 4a can be engaged with and detached from a locking piece 2a located at an eccentric position of the cam gear 2.

The cam lock lever 28 has guide grooves 28b, 2
Guide pins 1u and 1t are inserted through 8c and can be reciprocated in the directions of arrows C and D, and the cam lock lever spring 27 wound around the shaft 1b and the engagement portion 4c of the trigger lever 4 are connected to the engagement shaft 28d is pinched, and in conjunction with the rotation of the trigger lever 4, the arrow C,
It is reciprocated in the D direction. The cam lock lever spring 27 is in an energy storage state using the spring hook 4d of the trigger lever 4 as a fulcrum.

The interlocking lever 15 has its guide grooves 15b, 15
Guide pins 1r and 1s are inserted through C and can be reciprocated in the directions of arrows C and D, and are biased in the direction of D by a return spring 23 to act as fast-forward operating levers and rewind operating levers (not shown). pressed down,
It is displaced in the direction of arrow C.

The switch lever 16 is connected to A and B by a pivot shaft 16 that passes through a guide groove 1v on the main chassis.
The pivot shaft 16b is also inserted into the engagement groove 9d of the standby lever 9. That is, the switch lever 16 is displaced in the directions of arrows A and B by the swinging of the standby lever 9, and is also rotatable about the pivot shaft 16b.

Reference numeral 26 designates a solenoid switch as an operating switch for the song interval detection circuit, which is located in a solenoid circuit (not shown), and is normally in the OFF state when the contact portion 16a contacts the contact portion 26a as the switch lever 16 rotates. Turns on.

When the fast-forward operation lever and rewind operation lever (not shown) are pressed from a stopped state, they are locked in the operation state by a mechanical lock mechanism (not shown), and enter the fast-forward and rewind states, respectively. When the fast forward operating lever or the rewind operating lever is pressed in the reproduction mode, the switch lever 16 is rotated via the interlocking lever 15, and the solenoid switch 26 is turned on. This causes solenoid 2
6 starts to be energized, and the fast forward operating lever and rewind operating lever are locked by the attraction force of the solenoid 26.

Next, the operation of the switch opening/closing operation mechanism of the present invention having the above configuration will be explained. The timing lever 5 is biased clockwise by the trigger spring 25.
The cam gear 2 engages with the slope part of the timing cam 2b and presses the cam gear 2 in the direction of arrow F, but the locking part 4a of the trigger lever 4 engages with the slope part of the timing cam 2b of the cam gear 2. Because it is locked,
It is now impossible to rotate.

In addition, if the fast forward operation lever or rewind operation lever is operated in this stopped state, it will be locked by the lock mechanism (not shown) as described above.
Drives the reel stand at high speed to perform fast forward and rewind operations.

Since the switch lever 16 is moved in the direction of arrow A by the standby lever 9, the engaging portion 15a of the interlocking lever 15 enters the recess 16d of the switch lever 16, and the switch lever 16 cannot be rotated. . Therefore, the solenoid switch 26 cannot be energized.

Further, the locked fast forward and rewind operation levers are unlocked by operating a stop lever 14 by a lock mechanism (not shown) which is interlocked with a lock plate 12.

When the playback operation lever 13 is operated, the trigger lever 4 interlocked therewith rotates, and the engagement between the tip portion 4a and the engagement piece 2a is released.

The cam gear 2 is rotated counterclockwise by the timing lever 5, and the toothed portion of the cam gear 2 meshes with the drive gear 3, which is already rotating in the direction of the arrow E. Start rotating in the direction of arrow F. When the cam gear 2 starts rotating, the drive lever 7 is rotated by the drive cam 2c of the cam gear 2 in the direction of arrow E around the pivot shaft 1f, and presses the head plate 8 via the overstroke spring 24. , displace it in the direction of arrow C.

As the head plate 8 is displaced in the direction of the arrow C, the pinch roller lever 10 is rotated clockwise around the shaft 1e by a spring (not shown) that operates in conjunction with this, and the pinch roller lever 10 is pressed against the capstan shaft 11, and the reel (not shown) Move the drive mechanism in the direction of actuation. However, since the locking pin 9a is locked by the locking portion 5b of the timing lever 5, the connecting spring 18 has an increased biasing force.
Nevertheless, rotation of the standby lever 9 in the direction of arrow F is prevented.

The pinch roller lever 10 is connected to the head plate 8.
is rotated in the direction of arrow E, and the engagement portion 6d of the blocking lever 6 is pressed against the return spring 19 by the shaft 10a. However, the tip 9c of the locked standby lever 9 and the engaging portion 6a of the blocking lever engage with each other to prevent further pressing. Therefore, the pinch roller portion of the pinch roller lever 10 cannot be pressed against the capstan shaft 11. Similarly, a reel stand drive mechanism (not shown) is also blocked by a blocking lever.

Although the head plate 8 has already been displaced to a predetermined position in FIG. 2, the cam gear 2 meshes with the drive gear 3 and continues to rotate, and the overstroke spring 24
is being pushed even further. At this time, when a fast-forward operation lever or a rewind operation lever (not shown) is operated, the interlocking lever 15 interlocked with the fast-forward operation lever or rewind operation lever is pressed in the C direction. At this time, the engaging portion 15a enters the concave portion 16d of the switch lever 16, and moves the switch lever 16 to the contact portion 26a of the solenoid switch 26.
It is designed so that it cannot be rotated until it touches the . Therefore, the solenoid switch 26 is not energized, the fast forward/rewind lever is not locked, and when the user releases the lever, it returns to its original non-operating state. Further, when the fast-forward operation lever or the rewind operation lever is operated, each reel stand starts rotating at high speed in conjunction with the operation, and the respective reel units perform fast-forward or rewind operations until the hand is released.

When the cam gear 2 rotates a little more, the locking shaft 9a of the standby lever 9 and the locking portion 5b of the timing lever 5 are released, and the connection spring 18
The standby lever 9 rotates in the direction of arrow F due to the biasing force, and comes into contact with the locking pin 1g and stops. The switch lever 16 that interlocks with this has a pivot shaft 16b.
is displaced in the B direction. Further, the engagement between the engagement portion 6a of the blocking lever 6 and the engagement portion 9c of the standby lever 9 is released, and the blocking lever 6 is returned by the force of the head plate 8 which displaces the pinch roller lever 10 in the direction of the arrow E. It is pressed in the direction of arrow C against the spring 19.

When the blocking lever 6 is displaced in the direction of arrow C, a reel stand drive mechanism (not shown) starts operating, and the tape is fed at a constant speed by the pinch rollers that sandwich the tape and the capstan shaft 11 rotating at a constant speed. It is wound on a reel stand. Cam gear 2
At the position where the engagement with the drive gear 3 is completed, the above-mentioned regeneration mode position locking piece 2d is locked, and the position shown in FIG. 3 is reached.

In this state, the drive lever 7 is over the maximum diameter part of the drive cam 2c of the cam gear 2, so it receives the biasing force of the return springs 17 and 18 in the direction of arrow D via the overstroke spring 24, and Sign F
is pressed to rotate in the direction, thereby
The slope of the drive cam 2c is pressed, and the cam gear 2 is urged to rotate in the direction of arrow F, and this rotation is prevented by the locking piece 28a of the cam lock lever 28, which locks the cam gear 2 in the regeneration mode locking piece. It is received by locking 2d.

When the fast forward or rewind operating lever is operated in this playback mode state, the engaging portion 15a of the interlocking lever 15 that is linked to this presses the engaging portion 16c of the switch lever 16 displaced in the direction of arrow B, and the switch is activated. Rotate the lever 16 in the direction of arrow F,
Pressing the engaging portion 26a of the solenoid switch 26 at part a to energize the solenoid,
Fast forwarding or rewinding is performed by driving the reel stand at high speed. By energizing the solenoid 26, the fast forward or rewind operation lever is locked.

Further, due to the interlocking mechanism (not shown) of the interlocking lever 15, the camlock lever 28 moves in the C direction slightly against the biasing force of the camlock lever spring 27, thereby regenerating the locking piece 28a and the aforementioned cam gear 2. The locking with the mode position locking piece 2d is released,
The locking piece 28a of this cam lock lever 28 locks another locking piece 2e for the inter-track detection mode position. As a result, the cam gear 2 rotates slightly in the direction of the arrow F, and the engaging portion of the drive lever 7 engages the drive cam 2.
It falls from the maximum diameter part of c to the inter-track detection position 2c'.
As a result, the head plate 8 is slightly displaced in the direction of arrow D, the pinch roller lever 10 is returned to the direction of F, and the reel stand low-speed drive mechanism is released, and the tape remains in contact with the magnetic head in the fast forward or rewind direction. The magnetic tape is fed at high speed, and the track interval detection mechanism begins to operate. This is the inter-song detection mode state shown in FIG.

When the song interval detection circuit detects a song interval, a switch in the solenoid circuit (not shown) is turned off, the solenoid is released from adsorption, and the fast forward or rewind operation lever is unlocked and returned to its original non-operating position. let At this time, the interlocking mechanism (not shown) of the interlocking lever 15 causes the cam lock lever 28 to
returns to the playback mode position shown in Figure 3,
The locking piece 28a of the cam lock lever 28 releases the locking piece 2e for the between-track detection mode of the cam gear 2, and the locking piece 2e for the reproduction mode is released instead.
Return to the position where d is locked. As a result, the cam gear 2 receives the biasing force of the return spring 17 of the head plate 8, once returns to the stop position, is activated again by the biasing force of the trigger spring 25 of the timing lever 5, and similarly enters the regeneration mode state. It's getting old.

<Effects of the invention> As described above, according to the invention, a mode switching mechanism is provided in which the mode is switched by moving a magnetic head, etc. to a predetermined position by the rotational force of a cam gear having a drive cam coaxially with the drive cam. and a song interval detection circuit, a timing cam being provided coaxially with the cam gear, and timing setting means for following the timing cam and setting an operation timing of an operating switch of the song interval detection circuit; After the magnetic head etc. have moved to the predetermined position, the actuation switch is made operable by the timing setting means that follows the timing cam, so that the playback operation lever and the fast-forward operation lever are activated. Even if both are pressed at the same time from a stopped state, the operating switch of the song interval detection circuit will not operate and the fast forward operation lever will not be locked. Therefore, even if the drive torque is insufficient as in the conventional case, it is easy to do so. It is possible to return to the original state.

[Brief explanation of the drawing]

1 to 4 are plan views of essential parts of an embodiment of the present invention, in which FIG. 1 is a stop mode, FIG. 2 is a state on the way from stop mode to playback mode, and FIG. 3 is a playback mode. mode, and FIG. 4 shows the inter-track detection mode, respectively. 2...Cam gear, 2c...Drive cam, 2b...
Timing cam, 8...Head plate, 26...
...Solenoid switch.

Claims (1)

[Claims for Utility Model Registration] It has a mode switching mechanism and a song interval detection circuit for switching modes by moving a magnetic head, etc. to a predetermined position by the rotational force of a cam gear having a drive cam coaxially therewith. A switch opening/closing operation mechanism for opening and closing an operating switch of the song interval detection circuit of a tape recorder, etc., wherein a timing cam is provided coaxially with the cam gear, and the timing cam is driven by the timing cam to detect the song interval. A timing setting means is provided for setting an operation timing of an operating switch of the circuit, and after the magnetic head etc. has moved to the predetermined position, the operating switch is set to an operable state by the timing setting means that follows the timing cam. A switch opening/closing operation mechanism characterized by: