JPS63121156A - Tape recorder - Google Patents

Abstract

PURPOSE:To house and arrange a gear system in a small space, by arranging a driving gear, a first notch gear, and a second notch gear respectively so as to enclose the periphery of an intermediate gear. CONSTITUTION:Since the driving gear 46, the first notch gear 38, and the second notch gear 39 are arranged so as to enclose the periphery of the intermediate gear 45, both notch gears 38 and 39 with different function are driven rotatably respectively by one intermediate gear 45 being always driven rotatably by the driving gear 46. And the driving gear 46 is also the gear to transfer a driving force to a pair of reel bases. In such way, it is possible to house and arrange the driving gear for driving the reel base required for a tape recorder, the first notch gear 38 for switching the reproducing (recording) mode, and the second notch gear 39 for switching a tape feeding direction, in the small space centering the intermediate gear 45.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Field of industrial application B. Overview of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem F. Effect G. Embodiment G. Outline of operation of tape drive system and tape recorder (Figures 2 and 3) G2 Explanation of the structure of the playback/stop switching mechanism (Figures 1, 4 to 5E) G3 Description of the structure of the tape running direction switching mechanism (Figures 1, 5E)
(Figs. 4 to 5E) G4 Explanation of the operations of the playback/stop switching mechanism and the tape running direction switching mechanism (Figs. 4 to 5E) The present invention relates to a tape recorder that is most suitable for application to a recorder, and in which switching of the playback (recording) mode and switching of the tape running direction are performed by partially toothed gears.

B. Summary of the Invention The present invention provides a drive system that selectively transmits driving force to a pair of reel stands in a tape recorder in which switching of the playback (recording) mode and switching of the tape running direction are performed by toothless gears. gear, a first partially toothed gear that drives a drive rod for switching the playback (recording) mode, and a second partially toothed gear that drives a switching rod for switching the tape running direction, respectively, around the intermediate gear. The first partially toothed gear and the second partially toothed gear are each intermittently rotated by the intermediate gears that are arranged so as to surround each other and are constantly driven to rotate by the drive gear, so that the function is achieved by one intermediate gear. In this system, two partially toothed gears having different numbers of teeth can be driven to rotate, and these gear systems, which are essential for a tape recorder, can be housed in an extremely small space.

C. Prior Art Conventionally, there have been reverse type tape recorders that drive a drive rod by intermittently rotating a partially toothed gear to switch between playback (recording) mode and stop mode. Ta. There is also a device in which a switching rod is driven by rotating an intermittent gear intermittently to selectively switch the running of the tape between normal running and reverse running. As a device having both of these functions, a drive gear rotationally driven by a motor is provided, a first intermediate gear is constantly rotationally driven by this drive gear, and the first intermediate gear The tooth gear is intermittently rotationally driven to drive the drive rod, a second intermediate gear that is constantly rotationally driven by the drive gear is provided, and the second intermittent gear is intermittently driven by the second intermediate gear. There was one in which the switching rod was driven by rotation.

D Problems to be Solved by the Invention However, conventionally, when switching the playback (recording) mode and switching the tape running direction using partially toothed gears, the first and second partially toothed gears are rotated intermittently. Since dedicated first and second intermediate gears are provided for driving, the number of parts increases and the structure becomes complicated. Furthermore, when storing and arranging gear systems essential to a tape recorder, such as a drive gear, a rain intermediate gear, and a re-dentation gear, an extremely large space is required, making it difficult to downsize the tape recorder.

Therefore, the present invention enables two partially toothed gears having different functions to be intermittently rotated by one intermediate gear, and also allows these gear systems to be housed in an extremely small space.

E Means for Solving Problems The present invention provides a drive gear that is rotationally driven by a motor and selectively transmits driving force to a pair of reel stands, an intermediate gear that is constantly rotationally driven by this drive gear, and a first partially toothed gear that is intermittently rotationally driven by an intermediate gear to drive a drive rod for switching a playback (recording) mode; and a switching rod that is intermittently rotationally driven by the intermediate gear and drives a drive rod for switching a tape running direction. The driving gear, the first partially toothed gear, and the second partially partially toothed gear are respectively arranged to surround the intermediate gear.

F Function According to the present invention, since the drive gear, the first partially toothed gear, and the second partially toothed gear are arranged so as to surround the intermediate gear, one gear that is constantly rotationally driven by the drive gear is Re-dentation gears having different functions are intermittently rotated by the intermediate gear.

The drive gear is also a gear that selectively transmits the driving force to the pair of reel stands, so the drive gear for driving the reel stand and the first toothless gear for switching the playback (recording) mode are essential for tape recorders. and a second partially toothed gear for switching the tape running direction are housed in an extremely small space centered around the intermediate gear.

G. Embodiment Hereinafter, an embodiment in which the present invention is applied to an auto-reverse compact tape recorder using a compact cassette will be described with reference to the drawings.

G. First, the tape running drive system and the general operation of the tape recorder will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows the tape running drive system of this tape recorder, in which a cassette 4 containing a magnetic tape 3 wound around a pair of left and right reel hubs 1.2 is mounted on a chassis 6.
It is mounted horizontally on the top of the

At the top of the chassis 6, a pair of left and right reel stands 7.8, a capstan 9.10, a pinch roller 11.12, a magnetic head 13, etc. are provided, and the reel hubs 1.8 of the cassette 4 mounted on the chassis 6 are provided. 2 is engaged with the reel stand 7.8, and the magnetic tape 3 is passed onto the capstan 9.10 and the magnetic head 13. In addition, on one side of the chassis 6, there is a playback button 15 consisting of a feather touch type push button.
A stop port 16, a tape running direction switching button 17, etc. are provided, and the front surface of the chassis 6 is provided with a fast forward/rewind button 18 consisting of a sliding operation button.

Next, as shown in FIGS. 2 and 3, at the bottom of the chassis 6 there is a flat and thin motor 21 installed coaxially with the reel stand 8, and a capstan 9, which is fixed to the lower end of the capstan 10. A capstan pulley 22.23 which also serves as a flywheel, an intermediate pulley 24 attached to an approximately intermediate position of the reel stand 7.8, and a reversing pulley 25 disposed at a portion of the capstan pulley 23 are provided. And each of these pulleys 22, 23, 24, 25 and motor 2
An elastic belt 27 is wound around the first drive pulley 26.

On the other hand, the reel stand 7 attached to the upper part of the chassis 6
．． Reel stand gears 30, 31 are formed on the outer periphery of the reel stand 7.8, and an FR first idle gear 33 and an FR idle gear 33 for fast forwarding and rewinding the magnetic tape 3 are located between the reel stand 7.8.
An R second idle gear 34 is provided. Also, between the reel stands 7.8, there is an NR idle gear 35 and an NR intermediate gear 3 for normal running and reverse running of the magnetic tape 3.
6 is provided. Furthermore, at the bottom of the chassis 6 is a first toothless gear 3 for switching between regeneration mode and stop mode.
8, a second partially toothed gear 39 for switching between normal running and reverse running of the magnetic tape 3, and a switching drive gear 40 for intermittently rotationally driving these gears.

When the tape recorder operates the playback button 15 and the fast forward/rewind button 18, a power switch (not shown) is activated.
is inserted, the motor 21 is rotated at a constant speed, and the drive pulley 2
6 is rotationally driven in the direction of arrow a in FIG.
3 are configured to be rotated in the directions of arrows b, c, and d, respectively.

Then, when you operate the fast forward rewind button 18 to the fast forward side,
Due to the mechanical operation of a fast forward/rewind switching mechanism (not shown), the FR first idle gear 3 is connected to the FR drive gear 42 formed on the outer periphery of the intermediate pulley 24, as shown by the solid line in FIG.
3 is engaged, and this FR first idle gear 33
The FR second idle gear 34, which is always engaged with the reel stand gear 30 of one reel stand 7, is selectively engaged with the reel stand gear 30 of one reel stand 7.

As a result, one reel stand 7 is driven to rotate at high speed in the direction of arrow e, and a fast-forward mode is entered in which the magnetic tape 3 is run in the direction of arrow f and wound around one reel hub 1 at high speed.

Meanwhile, fast forward and rewind! I] When 18 is operated to the rewinding side, the PR first idle gear 33 selectively engages with the FR drive gear 42 and the reel stand gear 31 of the other reel stand 8, as shown by the dashed line in FIG. be done. As a result, the other reel stand 8 is driven to rotate at high speed in the direction of arrow g, and the magnetic tape 3 is run in the direction of force of arrow f'.
It enters rewind mode, which winds at high speed. Note that when the fast forward/rewind 1018 is operated to the neutral position in the above-mentioned fast forward mode and rewind mode, the FR first and second idle gears 33, 34 are returned to the neutral position and the stop mode is entered.

Next, when the playback button 15 is pressed, the intermediate gear 45 is switched by the integrated drive gear 44 in the same axis as the intermediate boo 1J24.
The switching drive gear 40, which is constantly rotationally driven integrally with the
The first partially toothed gear 38 is selectively engaged by a regeneration/stop switching mechanism 43 to be described later, and the first partially partially toothed gear 38 is driven half a rotation. Then, the NR which is provided on the same axis as the intermediate pulley 24 and is rotationally driven in the same direction as the intermediate pulley IJ24 via a torque limiter (not shown).
NR file gear 3 constantly engaged with drive gear 46
5 is selectively engaged with the NR intermediate gear 36, which is always engaged with the reel base gear 30 of one reel base 7, as shown by the solid line in FIG. At the same time, the magnetic head 1
3 comes into contact with the magnetic tape 3, and a pinch roller 11 is pressed against one capstan 9. As a result, one reel stand 7 is rotationally driven in the direction of the arrow e, the magnetic tape 3 is run in the direction of the arrow f and is wound on one of the reel hubs 1, which enters the normal playback mode, and the magnetic head 13 performs normal playback. .

Next, in normal playback mode, press tape running direction switch button 1.
7 or when the normal running of the magnetic tape 3 reaches the end of the tape, the tape running direction switching mechanism 4 described later is activated.
7, the second partially toothed gear 39 is selectively engaged with the switching drive gear 40, and the second partially partially toothed gear 39 is driven half a rotation. Then, the NR file gear 35 is selectively engaged with the reel stand gear 31 of the other reel stand 8 as shown by the dashed line in FIG.
The pinch roller 11 is separated from the capstan 10, and the pinch roller 12 is pressed against the other capstan 10. As a result, the other reel base 8 is rotationally driven in the direction of the arrow g, and the magnetic tape 3 is run in the direction of the arrow f'.
The magnetic head 1 enters the reverse playback mode where the
3, reverse playback is performed. Note that when the tape running direction switching button 17 is pressed in the reverse playback mode, the second partially toothed gear 39 is driven half a rotation again, and the mode returns to the normal playback mode.

Then, when the stop button 16 is pressed in the above-mentioned normal reproduction mode and reverse reproduction mode, the first partially toothed gear 38 is again driven by half a rotation. Then, the NR file gear 35 is returned to the neutral position, and the magnetic head 13 and the pinch roller 11 or 12 are returned to the stop mode.

In addition, this tape recorder operates in a single reciprocating mode in which the magnetic tape 3 is stopped after normal running and then in reverse running, and in a continuous mode in which the magnetic tape 3 is run continuously in normal running and reverse running repeatedly. mode, and in the case of 1 reciprocating mode, when reverse running reaches the end of the tape, the first
The second toothless gear 38 is driven half a turn and automatically enters the stop mode, and in the continuous mode, when reverse travel reaches the end of the tape, the second toothless gear 39 is driven half a rotation and automatically enters normal travel. become.

02 Next, the details of the structure of the regeneration stop switching mechanism 43 will be explained with reference to FIGS. 1 and 4 to 5E. Note that FIGS. 1 and 5A to 5E are views seen from the bottom side.

First, as shown in FIG. 4, a drive rod 50 is disposed at the bottom of the chassis 6 in the front and back direction. This drive rod 50 has a substantially L-shape, and is configured to be able to freely reciprocate in the directions of arrows h and h by having an elongated hole 52 guided by the rotating shaft 51 of the first partially toothed gear 38 implanted in the chassis 6. has been done. A return spring 53 is stretched between the drive rod 50 and the chassis 6, and the return spring 53 biases the drive rod 50 back in the direction of arrow h'.

A cam contact portion 54 made of a bent piece bent downward is formed on one end side 50a of the drive rod 50. Further, the other end side 50b of the drive rod 50 is formed almost symmetrically on the left and right sides, and a pair of left and right restriction parts 56 and 57 made of projecting pieces are provided on both sides of the notch 55 formed on the other end side 50b. It is being

Further, a linear spring 58 having a substantially U-shape is attached to the center of the other end side 50b of the drive rod 50, and both ends 58a and 58b of this spring 58 protrude toward the notch 55 side.

A protrusion 59 that protrudes upward is provided at the center of the other end side 50b of the drive rod 50, and a pair of drive pins 60 and 61 are fixed to both sides of the end so as to protrude toward the top of the chassis 6. There is. Note that both drive pins 60 and 61 are fitted into a pair of U162 and 63 provided on the chassis 6, and the negative U groove 62 also serves as a guide for the drive rod 50.

Next, as shown in FIGS. 1 and 5A to 5E, the first partially toothed gear 38 is rotatably supported by a rotating shaft 51 at the lower part of one end side 50a of the drive rod 50. . A cam portion 65 is integrally formed in the center of the upper surface of the first partially toothed gear 38, and a drive rod 50 is attached to the outer peripheral surface of the cam portion 65.
The cam abutting portion 54 is configured to be in contact with the cam abutting portion 54 of the cam abutting portion 54 .

The upper part 65 has a first protrusion 6 that largely protrudes from the center.
5a and a second protrusion 65b that protrudes slightly. Further, on the outer periphery of the first toothless gear 38, a first toothless portion 66 for playback mode and a second toothless portion 67 for stop mode are formed with an offset of 1800 degrees from each other. The toothless region θ8 of the first toothless portion 66 is set larger than the toothless region θ2 of the second toothless portion 67. Further, on the lower surface of the first partially toothed gear 38, in the vicinity of the re-toothed portions 67 and 66, a lock pawl 68 for the regeneration mode and a lock pawl 69 for the stop mode, each consisting of a protrusion, are integrally molded.

Next, a lock lever 71 is pivotally supported near the first partially toothed gear 38 at the bottom of the chassis 6 by a shaft 72 implanted in the chassis 6 so as to be swingable in the directions of arrows i and i'.
It is urged to rotate in the direction of arrow i by a return spring 73 stretched between it and the chassis 6. This lock lever 71 is a lock arm portion 7 to which the lock claws 68 and 69 come into contact.
4, an arcuate elastic arm portion 75 pressed by the lock claws 68, 69, and a holding arm portion 76 are integrally molded from synthetic resin. The lock arm part 74 and the elastic arm part 75 are formed in a substantially dogleg shape,
It is inserted into the lower surface side of the first partially toothed gear 38. Further, a movable iron core 78 is attached to the tip of the holding arm portion 76 by a shaft 77.
is attached so that it can swing freely. Note that the holding arm portion 76
A pin 79 is integrally molded at the tip of the bottle 79, and this bottle 79 is inserted into a hole 80 formed in the chassis 6. A movable iron core adsorption type solenoid 81 is disposed in the lower part of the chassis 6 for adsorbing the movable iron core 78 and holding the lock lever 71 in a reciprocating state in the force direction of arrow i'.

03 Next, the structure of the tape running direction switching mechanism 47 will be explained in detail with reference to FIGS. 1 and 4 to 5E.

First, as shown in FIG. 4, a switching lever 83 is provided at the bottom of the chassis 6 and between the reel stands 7.8.

This switching lever 83 is connected to a circular hole 84 formed in the chassis 6.
At the outer periphery of the NR drive gear 46, arrows j, j
' direction, and the upper surface of one end of the N
The R file gear 35 is rotatably supported and constantly engaged with the NR drive gear 46. At the other end of the switching lever 83, a pressed portion 85 consisting of a projecting piece and a pair of left and right restricted portions 86 and 87 on both sides thereof are formed symmetrically. The other end of the switching lever 83 is located within the notch 55 of the drive rod 50, and the pair of restricted portions 86
．． 87 is arranged so as to be sandwiched between the pair of restriction parts 56 and 57.

Therefore, both ends 58a and 58b of the spring 58 are located on both sides of the pressed portion 85 of the switching lever 83.

Next, as shown in FIG. 4, a switching rod 90 is disposed between the chassis 6 and the other end 50b of the driving rod 50 so as to be substantially perpendicular to the driving rod 50. As shown in FIG. This switching rod 90 can be moved between the normal position iN shown by the solid line and the reverse position WR shown by the - dotted chain line by guiding the elongated hole 93.94 onto the guide shaft 9192 which also serves as a bearing for the capstan 9.10. It is configured to be able to freely reciprocate in the 1 and ' directions. A spring pressing portion 9 consisting of a protrusion is located approximately in the center of the switching rod 90.
5 is provided, and this spring pressing portion 95 presses the spring 5.
It is inserted between both ends 58a and 58b of 8. Further, a protrusion 96 extending toward the second partially toothed gear 39 is provided at one end of the switching rod 90, and a cam hole 97 is formed in the protrusion 96. A pair of regulating pins 98 and 99 are fixed to the switching rod 90 so as to protrude toward the upper part of the chassis 6.

Next, as shown in FIGS. 1 and 5A to 5E, the second partially toothed gear 39 is rotated by a rotating shaft 101 implanted in the chassis 6 at the lower part of the protrusion 96 of the switching rod 90. It is freely supported. A roller 102 is pivotally supported on the upper surface of the second partially toothed gear 39 eccentrically from the center, and this roller 102 is engaged in a cam hole 97 of the switching rod 90.

Further, on the outer periphery of the second partially toothed gear 39, a partially toothed portion 103 for normal travel and a partially toothed portion 104 for reverse travel are formed so as to be offset by 180@ from each other. Further, on the lower surface of the second partially toothed gear 39, approximately 9
A lock pawl 105 for normal travel and a lock pawl 106 for reverse travel, each consisting of a protrusion offset by 0°, are integrally molded. By the way, this second partially toothed gear 39
and the first partially toothed gear 38 and the intermediate pulley 24,
They are arranged to surround the switching drive gear 40, respectively.

Next, at the bottom of the chassis 6 and near the second partially toothed gear 39, a lock lever 108 is attached to a shaft 10 embedded in the chassis 6.
Arrow 1 by 9. The lock lever 108 is rotatably supported in the direction of the arrow "1" by a return spring 110 stretched between the chassis 6 and the lock lever 108. A lock arm portion 111 to which the locking arm 106 is abutted, an arc-shaped elastic arm portion 112 pressed by the lock claws 105 and 106, and a holding arm portion 113 are integrally molded from synthetic resin. Lock arm part 111 and elastic arm part 112
is formed into a substantially dogleg shape and is inserted into the lower surface side of the second partially toothed gear 39.

Further, a movable iron core 115 is swingably attached to the tip of the holding arm portion 113 by a shaft 114.

Note that a pin 116 is integrally formed at the tip of the holding arm portion 113, and this pin 116 is inserted into a hole 117 formed in the chassis 6.

A movable iron core adsorption type solenoid 118 is arranged in the lower part of the chassis 6 to adsorb the movable iron core 115 and hold the lock lever 108 in a reciprocating state in the direction of arrow β'.

04 Next, the details of the operations of the playback stop switching mechanism 43 and the tape running direction switching mechanism 47 will be explained with reference to FIGS. 4 to 5E.

First, FIG. 5A shows the stop mode. That is, the movable iron core 78 of the holding arm portion 76 of the lock lever 71 is attracted to the magnet 81a of the solenoid 81, so that the lock lever 71 is held in a reciprocating state in the direction of arrow l''. As a result, the stop mode lock pawl 69 of the first partially toothed gear 38 comes into contact with the tip of the lock arm portion 74, and the first partially toothed gear 38 is locked in the stop mode position. Therefore, the second toothless portion 67 for the stop mode of the first toothless gear 38 is opposed to the switching drive gear 40 . In the stop mode position, the second
The protrusion 65b faces toward the cam contact portion 54 of the drive rod 50. Therefore, the drive rod 50, which is biased backward in the direction of the arrow h' by the return spring 53, has its cam contact portion 54
is stopped at the return position S where it abuts on the second protrusion 65b.

Note that the position of the second protrusion 65b is shifted laterally from a straight line passing through the rotating shaft 51 in the reciprocating direction of the drive rod 50. In this way, the drive rod 50 is moved back to the return position S in the direction of arrow h' as shown by the dashed line in FIG.
The protrusion 59 and the re-driving bins 60, 61 on the other end side 50b are also moved back.

Therefore, the magnetic head 13 and the pinch roller 11 or 1
2 are not driven and are spaced apart from the magnetic tape 3 and capstan 9 or 10.

Further, as the drive rod 50 moves back in the direction of arrow h', the pair of restricting portions 56 and 57 of the drive rod 50 move toward the switching lever 83.
Because it comes into contact with the pair of regulated parts 86 and 87 at the same time,
The switching lever 83 is held at the neutral position.

Next, when you press the playback button 15, the signal causes the motor 2 to
1 starts rotating, and a few seconds later, solenoid 81
is instantly energized. Then, as shown in FIG. 5B, a repulsive force of the movable iron core 78 is generated in the magnet 81a, the attraction of the movable iron core 78 is released, and the lock lever 71 is moved forward in the direction of arrow i by the return spring 73. Note that when the pin 79 of the holding arm portion 76 comes into contact with the side edge of the hole 80, forward movement of the lock lever 71 in the direction of arrow i is stopped. This forward movement disengages the lock arm portion 74 from the lock pawl 69, and the first partially toothed gear 38 is unlocked at the stop mode position.

Here, since a return force is applied to the drive rod 50 in the direction of arrow h' by the return spring 53, the second protrusion 65 of the cam portion 65 is biased by the cam contact portion 54 of the drive rod 50.
b is pressed. Therefore, at the moment when the first partially toothed gear 38 is unlocked, the return spring 53 causes the drive rod 5 to
0 and the arrow m to the first toothless gear 38 via the cam portion 65.
An initial mechanical rotational force in the direction is applied, and the first partially toothed gear 38 is engaged with the switching drive gear 40 . The switching drive gear 40 is always rotationally driven in the direction of the arrow n by the rotation of the intermediate pulley 24 together with the switching intermediate gear 45 via the drive gear 44, The first partially toothed gear 38 is driven to rotate in the direction of the arrow m.

When the first partially toothed gear 38 is rotated approximately 90 degrees, the lock pawl 69 locks onto the inner circumferential surface 75a of the elastic arm portion 75.
By moving along the elastic arm portion 75
is gradually pressed against its elasticity, and the lock lever 71 is moved back in the direction of arrow i' against the return spring 73, and the movable iron core 78 is attracted to the magnet 81a of the solenoid 81 again.

Then, when the first partially toothed gear 38 is rotated in the direction of the arrow m and driven half a rotation as shown in FIG.
At the same time as facing 0, the lock claw 68 for playback mode
is brought into contact with the tip of the lock arm portion 74, and the first partially toothed gear 38 is locked at the playback mode position. In this locked state, the vicinity of one end 66a of the first toothless portion 66 faces the switching drive gear 40.

As described above, while the first partially toothed gear 38 is driven half a rotation in the direction of the arrow m, the drive rod 50 is rotated by the cam portion 65.
The cam contact portion 54 of is pressed, and the drive rod 50 is moved forward in the direction of the arrow against the return spring 53. In the regeneration mode position where the first partially toothed gear 38 is locked, the first protrusion 65a of the cam portion 65 is connected to the cam contact portion 5 of the drive rod 50.
As a result, the drive rod 50 is stopped at the forward movement position P where the cam contact portion 54 is in contact with the first protrusion 65a. Note that the position of the first protrusion 65a is offset to the side relative to a straight line passing through the rotating shaft 51 in the reciprocating direction of the drive rod 50. In this way, the drive rod 50 is moved forward to the forward movement position P in the direction of the arrow as shown by the solid line in FIG. Redrive pin 60.
61 presses the pinch roller 11 or 12 onto the capstan 9 or 10.

By the way, when the drive rod 50 is moved forward as shown in FIG. 4, the pair of restricting portions 56,57 are simultaneously separated from the pair of restricted portions 86,87 of the switching lever 83. Here, the switching rod 90 has been moved to either the normal position N shown by the solid line or the reverse position R shown by the dashed line, but if it is moved to the normal position 7N, the switching rod 90 Since the spring pressing part 95 of 90 presses one end 58a of the spring 58 from the inside to the outside, the other end 58b of the spring 58 presses the pressed part 85 of the switching lever 83 from one side, whereby the switching lever 83 is swung in the direction of arrow j. Therefore, the NR file gear 35 of the switching lever 83 is engaged with the NR intermediate gear 36 as shown by the solid line in FIG.
The signal is transmitted to the reel stand gear 30 via the R idle gear 35 and the NR intermediate gear 36, and the reel stand 7 is rotationally driven in the direction of arrow e to enter the normal playback mode. In addition, switching rod 9
0 has been moved to the normal position N, the drive of the other pinch roller 12 is regulated by the other regulating pin 99 of the switching rod 90, and only the negative pinch roller 11 is pressed against the capstan 9. become.

Next, the above-mentioned switching rod 90 is connected to the tape running direction switching mechanism 47.
The magnetic tape 3 is selectively switched between normal running and reverse running. That is, although FIGS. 5A to 5E all show the normal running state, the lock lever 108 is held in a reciprocating state in the direction of the arrow L'', and the lock pawl 105 of the second partially toothed gear 39 for normal running is held. is in contact with the tip of the lock arm portion 111, and the second partially toothed gear 39 is locked at the normal position. In the normal position, the cam hole 97 of the switching rod 90 is
02, and the switching rod 90 is moved in the direction of the arrow to the normal position iiN shown by the solid line in FIG.

Here, when the tape running direction switching button 17 is pressed, the solenoid 118 is instantaneously energized by the signal. Then, the lock lever 108 is activated as shown by the dashed line in Fig. 5C.
The return spring 110 causes the arrow! to be moved in the direction of This forward movement disengages the lock arm portion 111 from the lock pawl 105, and the second partially toothed gear 39 is unlocked at its normal position. The second partially toothed gear 39 is engaged with the switching drive gear 40 and is driven to rotate in the direction of the arrow O, and when it has been driven half a rotation, the first
The lock pawl 106 for reverse running is brought into contact with the tip of the lock arm portion 111 by the same operation as the second partially toothed gear 38, and the second partially toothed gear 39 is locked in the reverse position. During this half-rotation drive, the switching rod 90 is rotated by the roller 102.
cam hole 97 is guided, and the switching rod 90 is moved in the direction of the arrow ' to the reverse position R shown by the dashed line in FIG. As a result, the switching lever 83 is swung in the direction of the arrow j', and the NR idle gear 35 of the switching lever 83 is engaged with the reel stand gear 31 as shown by the dashed line in FIG. The camera enters reverse playback mode, which rotates in the direction of the camera.

Note that when the tape running direction switching button 17 is pressed in the reverse reproduction mode, the solenoid 118 is momentarily energized again, and the second partially toothed gear 39 is again driven by half a rotation in the same manner as described above. As a result, the switching rod 90 is moved to the normal position N again, and the normal reproduction mode is entered.

Next, press the stop button 16 in the playback mode shown in Figure 5C.
The signal momentarily energizes the solenoid 81 again. Then, as shown in FIG. 5D, the lock of the first gear 38 in the regeneration mode by the lock lever 71 is released. Here, since a return force is applied to the drive rod 50 in the direction of arrow h' by the return spring 53, the biased first protrusion 65a of the cam portion 65 is pressed by the cam contact portion 54 of the drive rod 50. ing. Therefore, at the moment when the first partially toothed gear 38 is unlocked, the return spring 53 applies a mechanical initial rotational force to the first partially toothed gear 38 in the direction of the arrow m via the drive rod 50 and the cam portion 65. is granted,
The first partially toothed gear 38 is engaged with the switching drive gear 40 as shown in FIG. 5E. Then, the first partially toothed gear 38 is driven half a rotation by the same operation as described above, and is locked again at the stop mode position by the lock lever 71 as shown in FIG. 5A. During this half-rotation drive, the drive rod 50
is moved back in the direction of the arrow h' by the return spring 53, and the drive rod 50 is again stopped at the return position S to enter the stop mode.

As described above, in this tape recorder, the return spring 53 is used to move the drive rod 50 back when the first partially toothed gear 38 is unlocked to switch between the stop mode and the playback mode. As a result, an initial mechanical rotational force is applied to the first partially toothed gear 38 after unlocking. Therefore, without the need to provide a dedicated trigger spring or the like, a reliable trigger is applied to the first partially toothed gear 38, and the first partially toothed gear 38 is engaged with the switching drive gear 40.

Further, in this tape recorder, the toothless region θ1 of the first toothless portion 66 for the playback mode of the first toothless gear 38 is the toothless region θ1 of the second toothless portion 67 for the stop mode. Since it is set larger than θo, switching from playback mode to stop mode is instantaneously performed. That is, as shown in FIG. 5C, in the regeneration mode, the first toothless portion 66 of the toothless gear 38 of the shaft is connected to the switching drive gear 4 near one end 66a.
It is facing 0. Therefore, when the first partially toothed gear 38 is unlocked at the regeneration mode position as shown in FIG.
Due to the large toothless region θ, the gear is rotated in the direction of arrow m without being engaged with the switching drive gear 40, and is engaged with the switching drive gear 40 at a largely rotated position as shown in FIG. 5E. During this large rotation, the drive rod 50 moves to the forward position P.
, and is moved back in the direction of arrow h', and is instantly switched to stop mode.

Therefore, even if the fast-forward/rewind button 18 is operated in the playback mode, the playback mode is instantly switched to the stop mode at the moment of the operation, so the NR idle gear 35 etc. for the playback mode and the fast-forward/rewind button 18 are used for the playback mode. This prevents the PR first idle gear 33 and the like from being simultaneously engaged and locked by the NR drive gear 46 and the FR drive gear 42 of one intermediate pulley 24. Note that if the toothless region θ1 of the first toothless portion 66 is made larger than the first toothless region θ1, the first toothless region θ1
In some cases, the partially toothed gear 38 is rotated more than the stop mode position, and locking by the lock lever 71 becomes impossible. However, in this tape recorder, as shown in FIG.
Since the first partially toothed gear 38 is engaged with the switching drive gear 40 before starting to press the inner circumferential surface 75a of the elastic arm portion 75 of 71, the lock lever 71 is gradually and reliably returned to its original position by the lock pawl 68. As a result, the first partially toothed gear 38 is reliably locked in the stop mode position.

Furthermore, in this tape recorder, the first partially toothed gear 38 drives the drive rod 50 for switching between playback mode and stop mode, and the first partially toothed gear 38 drives the switching rod 90 for switching between normal travel and reverse travel. The NR drive gear 46 and the FR drive gear 42 (i.e., the intermediate boolean 1724) that selectively drive the pair of reel stands 7.8 are connected to the switching drive gear 40 (i.e., the switching intermediate gear 45). are arranged to surround the periphery. Therefore, the first partially toothed gear 38 and the second partially toothed gear 3 are connected by one switching drive gear 40.
9 are selectively driven, and the gear system for driving the reel stand 7.8 and the gear system for mode switching are housed in an extremely small space.

Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment (and various effective changes can be made based on the technical idea of the present invention).

For example, in the embodiment, the pair of reel stands are driven to rotate in both fast forwarding and rewinding, and in normal running and reverse running in the playback mode, but
This drive gear may be a drive gear dedicated to fast forwarding and rewinding, or a drive gear dedicated to normal travel and reverse travel, and in the embodiment, a lock lever driven by a solenoid locks and unlocks the first and second toothless gears. -, but various configurations are applicable to this. Furthermore, although only a playback function is shown in the embodiment, the present invention can be applied as is even if the device has a recording function.

Note that the present invention is not limited to an auto-reverse compact tape recorder using a compact cassette, but can be applied to various tape recorders.

H Effects of the Invention The present invention includes a drive gear that selectively transmits driving force to a pair of reel stands, a first partially toothed gear that drives a drive rod for switching playback (recording) modes, and a gear that switches the tape running direction. A second intermittent gear that drives the switching rod for the second interlocking gear is arranged so as to surround the intermediate gear, and the reinterlocking gear is intermittently rotated by the intermediate gear that is constantly rotationally driven by the drive gear. Since it is designed to drive, there is no need to provide two intermediate gears for each of the intermittent gears to rotate, and one intermediate gear can be used to rotate the re-interrupted gears, which have different functions. This allows the number of parts to be reduced and the structure to be simplified.

The drive gear is also a gear that selectively transmits the driving force to the pair of reel stands, so there is a drive gear for driving the reel stands, a first partially toothed gear for switching the playback (recording) mode, and a gear for switching the tape running direction. It is possible to store and arrange the second partially toothed gear for the tape recorder in an extremely small space centered on the intermediate gear. The recorder can be significantly downsized.

[Brief explanation of the drawing]

The drawings show an embodiment in which the present invention is applied to an auto-reverse compact tape recorder using a compact cassette, and FIG. 1 is an exploded perspective view of the playback stop switching mechanism and the tape running direction switching mechanism seen from the bottom side. Figure 2 is an exploded perspective view of the tape running drive system, Figure 3 is a plan view of the same as above,
FIG. 4 is a plan view of the playback/stop switching mechanism and the tape running direction switching mechanism, and FIGS. 5A to 5E are bottom views of essential parts for explaining the same operations. In addition, in the symbols used in the drawings, 7.8-・---------1.-- Reel stand 21-.
−・・−−−−・−−−−−・Motor 30.31−m
−・・−・Reel stand gear 33− ・−・−・・−
・---FR 1st idle gear 34---------...
・−・−・−・FR 2nd Idol Gi Ryo 35・−・−・−
・−・−NR idle gear 38−−−−−・・−−−
1-・-・-First partially toothed gear 39---------・-・-
−−−・−・Second partially toothed gear 40・・・−−−
1.----Switching drive gear 42.--1--
−−・−・−FR drive gear 43・−・−−−m−−・−
・−・−Reproduction stop switching mechanism 44−・−・−・・・・・−・
・・Drive gear 45・−・−−−−−−1・・−−−−
−・−・Switching intermediate gear 46−−−−−−−・・−−−
−・−・−・−NR drive gear 4'7'−−−・−・・−
・・・・−・Tape running direction switching mechanism 50・−・−
······························································−········································································································································· It is a switching rod.

Claims (1)

[Claims] A drive gear that is rotationally driven by a motor and selectively transmits driving force to a pair of reel stands, an intermediate gear that is constantly rotationally driven by this drive gear, and an intermediate gear that is intermittently rotated by this intermediate gear. A first partially toothed gear is driven to drive a drive rod for switching the playback (recording) mode, and a second partially toothed gear is intermittently rotationally driven by the intermediate gear to drive a switching rod for switching the tape running direction. A tape recorder comprising: a toothed gear; the drive gear, the first partially toothed gear, and the second partially toothed gear are respectively arranged to surround the intermediate gear.