JPH056578Y2 - - Google Patents

Description

[Detailed description of the invention] "Purpose of the invention" (Field of industrial application) The present invention relates to a mechanism for switching the switching drive gear of a cassette tape recorder to fast forward or rewind mode, and is particularly unnecessary for the switching drive gear. This invention relates to a drive gear switching mechanism that can smoothly switch gears without applying heavy loads.

(Prior art) In conventional cassette tape recorders, multiple motors are used as drive sources, and multiple plunger solenoids are used as operating mode switching mechanisms to electrically switch between play (PLAY) and fast forward (F/F). , rewind (REW), cue, review, etc.

On the other hand, in recent years, reverse-head cassette tape recorders have become mainstream, and in this type of equipment, forward side play, cue, review, pause and reverse side play, cue, It is necessary to perform actions corresponding to each operation such as review and pause.

(Problems to be solved by the invention) The above-mentioned conventional cassette tape recorder uses multiple motors as drive sources, which increases costs. Since this is a device that has to be operated, it must be driven by a large-capacity plunger, which has disadvantages such as high power consumption and increased operating noise. In addition, especially in the head reversing type, the mechanism is complicated and large, and the operability is not good.

In order to eliminate the above-mentioned drawbacks of the conventional device, the inventor of the present invention has proposed that it can be driven by a single motor, and that a single control cam gear can perform play, cue, review, pause on the forward side, and play, cue, review, and pause on the reverse side. Although we have separately proposed an operation mode setting mechanism for a cassette tape recorder that can set various operation modes such as pause, the present invention aims to provide a switching drive gear switching mechanism that is optimal for such an operation mode setting mechanism. In particular, the object of the present invention is to provide a mechanism that enables smooth switching without imposing unnecessary load on the switching drive gear.

"Structure of the invention" (Means for solving the problems) The drive gear switching mechanism of the cassette tape recorder according to the invention has a mechanism for switching the switching drive gear to fast forward or rewind mode. A switching cam gear having a cam portion that rotates in mesh with a drive gear such as a flywheel gear and moves a slider, which is always urged in a backward direction by the rotation, forward against the urging force. , a switching lever having an engaging part that engages with a cam part formed on the switching cam gear and swingable by a switching solenoid; and a switching lever for swingably holding the switching drive gear. The engagement pin of the retaining arm engages,
A bifurcated guide groove is formed on the slider to swing the holding arm into either fast forward or rewind mode, and a bifurcated guide groove is provided on the switching lever to allow the engagement pin to enter the guide groove. and elastic means for elastically controlling the engagement.

(Function) The holding arm that holds the switching drive gear has an engaging pin that engages with a bifurcated guide groove formed on the slider. It is located in the middle of the groove. When the solenoid is energized in a first pulse by the operating action and the switching lever swings, the switching cam gear meshes with the drive gear and starts rotating. Move forward against the urging force. Normally, the holding arm is biased so that the switching drive gear meshes with the reel stand on the take-up side, so as the slider moves forward, the engaging pin enters the fast-forward mode side of the bifurcated guide groove. . In this state, the switching cam gear is out of mesh with the drive gear, so by energizing the switching solenoid in this state, the switching lever engages the cam part of the switching cam gear, setting the fast forward mode. be done. When the power supply to the solenoid is stopped, the slider retreats due to its biasing force, the engagement pin returns to its original position, and the engagement between the switching lever and the switching cam gear is released, and the switching cam gear rotates to its original position. .

On the other hand, when the switching lever is swung by the first pulsed energization to the solenoid, and just before the switching cam gear starts rotating and moves the slider forward, a second pulsed energization is performed to the solenoid. The switching lever swings, and the engaging pin is pushed against the biasing force toward the take-up reel by the resilient means provided on the switching lever, so that as the slider moves forward, the engaging pin is pushed against the other side of the guide groove as the slider moves forward. (rewinding mode side) and maintaining the above-mentioned energized state, the switching lever and the cam portion of the switching cam gear engage, and the rewinding mode is set. In addition,
As mentioned above, when the power is turned off, everything returns to its original position.

(Embodiment) An example in which the drive gear switching mechanism for a cassette tape recorder according to the present invention is implemented in a magnetic head reversal type cassette tape recorder will be explained based on the drawings.

Figure 1 is a diagram showing the overall layout, as seen from the loading side of the cassette tape, and details of the chassis and other parts are omitted to simplify the diagram. .

Figure 2 is a plan view showing only the drive source relationship, Figure 3 is a plan view showing the relationship between the reel stand and idler, and Figure 4 is the relationship between the drive gear, control cam gear, direction arm, etc. FIG. Note that FIGS. 1 to 4 all show the forward stop state.

FIGS. 5A and 5B are perspective views showing the control cam gear, with A being a perspective view as seen from the top side, and FIG. 5B being a perspective view seeing from the bottom side.

Figure 6 is a perspective view of the direction arm, Figure 7 is a perspective view of the direction arm.
The figure is a plan view showing the engagement state between the direction arm and the direction slider, Figure 8 is a rear view showing the head reversing mechanism, and Figure 9 is a plane view showing the relationship between the direction slider and the pinch roller. 10 is a rear perspective view of the idler component, FIG. 11 is a plan view showing the fast forward and rewind switching mechanism, and FIGS. 12 to 15 show the relationship between the control cam gear and direction arm. FIG. 12 shows the forward stop position, and FIG. 13 shows the reverse stop position.

Fig. 14 is a plan view showing the reversal area of the head from forward to reverse, and Figs. 15 A to F are plan views showing the engagement positional relationship between the control cam gear and the engagement portion (pin) of the direction arm. and
A is the forward stop position, B is the forward play position, C is the forward cue position, D
indicates the reverse stop position, E indicates the reverse play position, and F indicates the reverse cue position. 16A to 16C are plan views showing the relationship between the control cam gear and the trigger lever, where A shows the stop position for both forward and reverse, B shows the play position for both forward and reverse, and C shows the forward and reverse positions. , shows the positional relationship of reverse queue and review, respectively.

17A to 17D are plan views showing the positional relationship between the idler component and the direction arm;
is the forward stop and play position,
B indicates the positional relationship between reverse stop and play, C indicates the positional relationship between forward cue and review, and D indicates the positional relationship between reverse cue and review. FIG. 18 is an operation timing chart of the first solenoid or the second solenoid accompanying each operation.

The basic structure of the drive gear switching mechanism of the cassette tape recorder according to the present invention is as follows:
In a switching mechanism for switching to fast forward or rewind mode, the operating action rotates in mesh with a drive gear 16 such as a flywheel gear, and is constantly biased in the backward direction by the rotation. The switching cam gear 24 has a cam portion 241 that moves the slider 39 forward against the biasing force thereof, and the switching solenoid 6 has an engaging portion 82 that engages with a cam portion formed on the switching cam gear. The switching lever 8, which is swung by the switch lever 8, is engaged with the engagement pin 93 of the holding arm 91 for swingingly holding the switching drive gear 9, and the holding arm is moved to either fast forward or rewind. A bifurcated guide groove 42 is formed on the slider 39 to allow the slider to swing in the mode, and the engaging pin 9 is provided on the switching lever 8.
A torsion spring 84 is provided as an elastic means for elastically controlling the engagement of the guide groove 3 into the guide groove 42.

Next, the specific configuration will be explained, but the overall configuration will be explained first.

First, to explain the drive source system, the first flywheel 1 and the second flywheel 2 are rotated by a motor 3 via a belt 4 that is stretched around the outer peripheral surface thereof in a substantially "S" shape. 1a and 2a each indicate a capstan. Reference numeral 5 designates a first solenoid, and its plunger 50 engages with the rear end of the trigger lever 7, which rotates about a shaft 70. As will be described in detail later, the trigger lever 7 is activated in response to an operation mode switching operation. 7. Reference numeral 6 designates a second solenoid as a switching solenoid, and its plunger 60 engages with the rear end of a switching lever 8 shaped like a "Y" that rotates around a shaft 80 as a fulcrum. By swinging the switching lever 8, the modes can be switched between fast forward (FF) and rewind (REW).

As shown in FIG. 2, a switching drive gear 9 for switching and driving the take-up reel stand 11 and the unwind reel stand 12 in the forward state is supported by a holding arm 91 that swings about a shaft 90. A pulley 92 is disposed coaxially with the flywheel 1, and is driven by a belt 10 suspended between the pulley 1b and a pulley 1b coaxially disposed with the first flywheel 1. Note that although the take-up reel stand 11 rotates via the intermediate gear 13, the switching drive gear 9 is always urged in the direction of meshing with the intermediate gear 13 (in the direction of arrow 9F). FIG. 3 shows the relationship between the idler component 14 and the switching drive gear 9, etc., and the idler component 14 is arranged to be swingable with a slide base 15 in between.
A magnetic head 26 is mounted on the slide base 15 and is always urged in a backward direction (downward in FIGS. 1 and 3) by a spring (not shown).
6 is brought into contact with the tape and removed from the tape by retreating.

As clearly shown in FIG. 4, the control cam gear 17 is rotated by the drive gear 16 coaxially provided on the first flywheel 1, but the control cam gear 17 has a toothless shape. In addition, as shown in FIG. 5, cam portions 18 and 19 are provided on the upper and lower surfaces.
are formed respectively. To specifically explain the configuration of the cam portion of this control cam gear 17, the control cam gear 17 is molded from engineering plastic, and the cam portion 18 on the upper surface side is approximately semicircular with the shaft 170 as the center. A cam 181 formed in the shape of a cam 181, a cam 182 shaped like a "dog" which is continuously formed at one end and slightly higher than the cam 181, a block cam 183 having a substantially trapezoidal shape, An arcuate cam 184 located on the outer periphery and an arcuate cam 185 lower than this
and an extrusion cam 186 formed at the tip of the shaft 170, and by rotation of the extrusion cam, the cut and raised portion 1 of the slide base 15 is
By pushing 52, the slide base 15 is moved forward against the elastic force. Note that 187 is a hole formed to correspond to the push-out cam 186, and the block cam 1
83 is formed at the edge of the hole. In addition, the cam portion 19 on the lower surface side has two stopper cams 191 and 192 formed at a predetermined interval on the outer periphery.
and the stopper cam 19 from the shaft 170.
It consists of a substantially rectangular block cam 193 extending between 1 and 192, and an "L" shaped cam 194 formed on the opposite side. Incidentally, an engagement pin 71 formed on the trigger lever 7 is adapted to engage with the cam portion 19 on the lower surface side, and the relationship between these will be explained later based on FIG. 16.

Reference numeral 20 denotes a direction arm that rotates around a shaft 200, and is biased clockwise by a coil spring 20a.As shown in FIG. 6, an engagement pin 231 is formed upwardly at one end 23. At the same time, a bifurcated groove 201 serving as an engagement groove is formed on the other end side. Further, a side wall portion 202 is formed on the side of the bifurcated groove 201, and an “L”-shaped locking piece 203 is formed downward from the side edge of the bearing portion. Near the outer edge of the central bent part, a low engagement pin 21 and a high engagement pin 22 protrude downward in the vicinity of the above-mentioned control cam gear 1.
The one end 23 is adapted to be engaged with a cam portion 18 on the upper surface side of the control cam gear 17, and swing by the rotation of the control cam gear 17, so that the one end portion 23 can be moved between four positions. Note that these relationships are explained in Part 1.
This will be explained later based on FIGS. 2 to 15.

In FIGS. 1 and 4, 24 is a switching cam gear formed in a toothless shape, and is connected to the drive gear 1.
6 and is driven to perform switching between fast forward (FF) and rewind (REW), the specific configuration of which will be explained later based on FIG. 11.

Direction slider 2 arranged so as to be able to slide on the chassis as shown in Fig. 7
An engagement groove 250 is formed on the bottom side of 5,
One end 2 of the direction arm 20 is attached to this.
The engagement pin 231 of No. 3 is engaged with the one end portion 23.
The direction slider 25 is adapted to slide as the direction slider 25 moves four positions. 8th
As shown in the figure, a head mounting block 27 is fixed to the slide base 15, and a magnetic head 26 is attached to this so as to be reversible by a reversing mechanism 28. This reversing mechanism rotates a gear 280 that meshes with a gear fixed to the rotating shaft of the magnetic head 26 via a lever 281 formed as a part thereof, and the magnetic head is reversed in a click manner by a spring 282. However, the lever 281 engages with an engagement hole 29 formed approximately in the center of the direction slider 25, and the magnetic head 26 is reversed by the slide of the direction slider 25. It is configured as follows.

Numerals 30 and 31 shown in FIG. 9 are pinch roller mechanisms, 30 is the reverse side, 31 is the forward side, and the pinch rollers 32 and 33 are the shaft 300,
Pinch arm 30 rotating around 310 as a fulcrum
1 and 311, respectively, and the pinch rollers are always urged to be in pressure contact with the capstans 1a and 2a.
1 and 311 are provided with pins 302 and 312, respectively, which are connected to the pinch roller control groove 3 formed in the direction slider 25.
4 and 35, respectively. Cut grooves 340 and 350 are formed in the pinch roller control grooves 34 and 35, respectively, for controlling whether or not the pinch roller is brought into pressure contact with the capstan.

FIG. 10 is a perspective view of the idler mechanism seen from the bottom side, and the idler gear 36 is composed of two gears 361, 362 and an intermediate gear 37, which are overlapped with each other via a friction member such as felt so as to rotate in a slip manner. However, the two gears 361 and 362 are pivotally supported at one end of the idler plate 38 which is formed in a substantially "V" shape, and this shaft pin 360
protrudes downward as an engagement pin. The intermediate gear 37 is pivotally supported by the other end of the idler plate 38. On the back side of the idler plate 38, a long engagement pin 380 is protruded from a bifurcated portion, and a support piece 381 extends from the base of the engagement pin 380. A short engagement pin 382 protrudes from the support piece 381.
is prominently formed. An engagement piece 383 is protruded from the rear end of the idler plate 38, and this engages the window hole 15 formed in the slider 15 as shown in FIG.
The idler component 14 is slidably engaged with an engaging piece 151 on the edge of the opening. In addition, at the base of this engaging piece 383, there is another pin 384 that engages with the edge of a window formed in the chassis.
is prominently formed. Further, the side wall portion 202 of the direction arm 20 has engagement pins 380, 38.
When the engaging pin 382 and the shaft pin 360 engage with the bifurcated groove 201, the idler component 1
4 is designed to be swing-controlled. This relationship will be described later based on FIG. 17.

As shown in FIG. 11, the switching cam gear 24
A pressing cam 241 for advancing the slide base 15 is formed on the upper surface, and a drive cam 242 and a stopper cam 243 are formed on the lower surface, and a guide cam 244 having a recess extending from the shaft portion to the middle thereof. A pin 82 extends from one end 81 of the switching lever 8.
are now engaged.

Reference numeral 39 denotes a slider that is slidably disposed on the underside of the chassis, and is always urged in the backward direction by a spring 43, and has a lever portion 40 on the rear end side and a pressing portion on the tip side. 41 are formed respectively, and the lever portion 40 engages with a pressing cam 241 formed on the switching cam gear 24, and when the lever portion 40 is pressed by the rotation of the switching cam gear 24, an elastic force is generated. We are moving forward against this. This slider 3
1 and 11 at the pressing part 41 by the forward movement of 9.
The brake plate 44 shown in the figure is moved forward against the resilient force to release the brakes on the reel stands 11 and 12. The brake plate 44 is PLAY
(FWD, RVS) and CUE, RVW (FWD,
RVS), the brake plate 44 is released by pushing up both left and right end surfaces of the brake plate 44 with the protrusions on the left and right upper ends of the slide base 15. This slider 39 has a substantially "Y"-shaped guide groove 42 formed on the back side, and an engagement pin 93 protruding from the tip of the holding arm 91 is engaged in the guide groove 42. . Then, depending on which side of the guide groove 42 the engaging pin 93 enters, the holding arm 91 is oscillated, and the driving gear 9 is rewinded to the reel stand 12.
Or it is made to mesh with the intermediate gear 13.

As shown in FIG. 11, the switching lever 8 is provided with a torsion coil spring 84 as a springing means on its shaft.
One end thereof is extended and held by the holding portion 83, and is adapted to engage with the engagement pin 93. That is, this switching lever 8 is always urged to rotate clockwise by a coil spring 45, and in a normal state, the tip of the torsion coil spring 84 is separated from the engagement pin 93, and the drive gear 9 is biased in the direction of arrow 9F, so when the slider 39 moves forward, the engagement pin 93 enters the right side of the guide groove 42, but the switching lever 8 is pulled by the second solenoid 6. When the slider 39 moves forward in this state, the torsion coil spring 84 contacts and presses the engagement pin 93, and the engagement pin 93 enters the left side of the guide groove 42.

Next, related mechanisms centering on the control cam gear 17 will be explained. In the explanation of the diagram, FWD is forward, RVS is reverse, CUE is cue, RVW is
indicates review, FF indicates first forward, and REW indicates rewind.

Figure 12 shows the location of FWD STOP.
The low engagement pin 21 and the high engagement pin 22 are located so as to straddle the arcuate cam 184. In this state, the engagement pin 231 protruding from one end 23 of the direction arm 20 is in the FWD STOP (PLAY) position, the direction slider 25 is in the position shown, and the pin of the FWD pinch arm is in the FWD STOP (PLAY) position. 31
2 enters the cut groove 350, and the FWD side pinch roller is in contact with the capstan.

FIG. 13 shows the position of RVS STOP, and the engagement pins 21 and 22 are in the positions shown. Only the pinch roller on the RVS side is in contact with the capstan. FIG. 14 shows that the control cam gear 17 is in the 12th position.
It shows the region where the magnetic head reverses from FWD to RVS when rotating in the direction of arrow 17F from the state shown in the figure.

15A to 15F show the positional relationship between the cam portion 18 of the control cam gear 17 and the engagement pins 21, 22 of the direction arm 20 according to each operation as shown in the figures.

16A to 16C are diagrams showing the relationship between the cam portion 19 on the back side of the control cam gear 17 and the trigger lever 7, and are shown as seen through from the cassette tape loading side. Figure A shows both FWD and RVS STOP.
Figure B shows the PLAY position for both FWD RVS, and Figure C shows the CUE or RVW position for both FWD RVS. The trigger lever 7 is formed in a substantially dogleg shape, with three peaks formed on the tip side, and an engagement pin 71 formed on the innermost peak, and an engagement pin 71 continuously extending outward. Locking part 72,
73 are formed respectively. The above engagement pin 7
1 is adapted to engage with the cam portion 19, and the locking portions 72 and 73 are configured to hold the locking piece 203 of the direction arm 20, as will be explained later.

FIG. 17 is a diagram showing the relationship between the direction arm 20 and the idler component 14 (FIG. 10), and in the figure, the engagement relationship between the bifurcated groove 201, which is an engagement groove, and each pin of the idler component 14. It is shown as. Figure 17A is from FWD STOP to FWD
Showing the engagement relationship leading to PLAY, slide base 1
5, the shaft pin 360 and the engagement pin 38
0 moves in the direction of the arrow and reaches the position shown by the imaginary line. Therefore, the idler gear 36 as a whole is 36
It will operate in the direction shown by F1. Figure 17B shows the engagement relationship from RVS STOP to RVS PLAY, and the idler gear 36 as a whole is 36F.
It operates in the direction shown in 2. Figure 17C shows the positional relationship between CUE and RVW in FWD.
In this mode, the pin 384 engages with the edge of the window 100 formed in a convex shape on the chassis, so the entire idler does not move forward. Figure 17D is
It shows the positional relationship between CUE and RVW in RVS, and in this mode, the above-mentioned another engagement pin 382
Since the shaft pin 360 and the shaft pin 360 are locked in the position shown in the figure, the entire idler will not move forward.

Next, an example of operation will be explained.

The control cam gear 17 is set to rotate once at a predetermined speed, and the timing at which the first solenoid 5 or the second solenoid 6 should be operated in accordance with each operation is computer programmed. FIG. 18 is a timing chart of these, and in the figure, S1 indicates the first solenoid 5, and S2 indicates the second solenoid 6.

To explain the operation of FWD PLAY in FIGS. 15 and 16, the drive gear 16 is located at the first missing tooth 171 of the control cam gear 17 and rotates, but as shown in FIG. 18, When the first solenoid 5 (S1) is energized in a pulsed manner for a predetermined period of time from time 0, which is the STOP state, the engagement pin 71 of the trigger lever 7 hits the cam 193, thereby causing a small rotation start. The cam gear 17 meshes with the drive gear 16 and rotates approximately half a rotation, and the low engagement pin 2
1 moves while sliding on the inner surface of the cam 182. During this movement process, the first solenoid 5 is energized for a second time as shown in FIG. Prevent arm 20 from rotating clockwise. This allows pin 31 of the forward side pinch arm to
2 is the cut groove 350 of the direction slider 25
The state corresponding to is maintained. Further, due to the holding of the locking piece 203 by the locking portion 73, the high engagement pin 22 is located inside the cam 185, and the control cam gear 17 rotates clockwise from the initial position in FIG. 16 is the second missing tooth 172
By being located at , the state shown in Figure 15B is reached,
At the same time, the cam 186 pushes up the cut and raised piece 152 of the slide base 15, thereby bringing the magnetic head 26 into contact with the tape and setting the FWD PLAY state. Note that the control cam gear 17 rotates a little due to the stopper operation, and the drive gear 16 is positioned at the first missing tooth 171 to reach the STOP position in FIG. 15A.
The state will be as follows.

In the FWD CUE state shown in Fig. 15C, the setting at startup is almost the same as the setting for PLAY above, but as is clear from Fig. 18, during the above operation, the second energization is performed. Therefore, the engagement pin 22 passes through the outer surface of the cam 185, resulting in the state shown in FIG. 15C. In the case of this FWD CUE, the first solenoid 5 is then continuously energized while the control cam gear 17 is rotating, thereby holding it as shown in FIG. 16C. In addition,
In this state, the tip 74 of the trigger lever 7 is in the front side of the locking piece 203 (the upper side of the locking piece 203 in FIG. 4), and the cut grooves 340 and 350 of the direction slider 25 are both pinned. 302 and 312, the pinch roller cannot move forward, and the tape is not pressed by the pinch roller. Furthermore, the engagement between the cam 186 and the cut and raised piece 152 of the slide base 15 is
Although it is slightly lowered than during PLAY, the magnetic head 26 is still in contact with the tape and detects the magnetically recorded portion of the tape (CUE).
can do. In addition, the FWD CUE mentioned above
The situation is the same for FWD RVW, and the second
The switching cam gear 24 is operated by the operation of the solenoid 6 (S2) to switch between FF (fast forward) and REW (rewind).

FIG. 15E shows the position of RVS PLAY. For example, in order to set from the FWD PLAY state in FIG. 15 to this RVS PLAY state, the position shown in FIG. As shown in the figure, the control cam gear 17 rotates clockwise, and the slide base 15 is lowered once by the cam 186 that engages with the cut-and-raised piece 152 of the slide base 15, thereby lowering the pinch roller 31 and the pinch arm 311. The pin 312 is disengaged from the cut groove 350, and the direction slider 25 is free to slide left and right, and then the direction arm 20 swings greatly about the shaft 200, and the direction slider 25 slides to the right in Fig. 12, and the magnetic head is reversed within the area shown in the figure to become RVS.
Similar to FWD PLAY, the magnetic head 26 comes into contact with the tape due to the engagement of the cam 186 and the cut-and-raised piece 152 of the slide base 15, and the RVS shown in FIG.
It will be in the PLAY state. During this process, the engagement pin 21 is low and can freely pass over the cam 183. Even in this state, the control cam gear 17 rotates slightly due to the STOP operation, resulting in the STOP state shown in FIG. 15D.

To change from the RVS STOP state shown in Fig. 15D to the RVS PLAY state shown in Fig. 15E, the control The cam gear 17 rotates about one revolution and enters the state shown in FIG. 15E. In RVS CUE, the state shown in FIG. 15F is set by energizing the first solenoid S1 at the predetermined timing shown in FIG.
This situation is also the same for RVS RVW.
Also, the relationship between the trigger lever 7 and the cam part 19 is the same as in the case of FWD described above, but RVS CUE
In the RVS and RVW, the locking piece 203 is locked and held on the locking portion 72 side of the trigger lever 7.

As shown in FIG. 18, in FF and REW, the first solenoid 5 (S1) and therefore the control cam gear 17 do not function, and the second solenoid 6 (S1) does not function.
This is done by operating the switching cam gear 24 by energizing the switch 2).

"Effect of the invention" According to the drive gear switching mechanism of the cassette tape recorder according to the invention, the engagement pin of the holding arm holding the switching drive gear engages in the middle of the bifurcated guide groove formed in the slider. matches,
When the slider is moved forward against the urging force by the rotation of the switching cam gear, the engagement pin enters into the guide groove, but normally the holding arm is arranged so that the switching drive gear meshes with the reel stand on the take-up side. Since it is energized, the engagement pin enters the fast-forward mode side of the bifurcated guide groove as the slider moves forward, and in this state, by energizing the switching solenoid, the switching lever moves to the switching cam gear. A fast forward mode can be set by engaging the cam portion. When the power supply to the solenoid is stopped, the slider retreats due to its biasing force, the engagement pin returns to its original position, and the engagement between the switching lever and the switching cam gear is released, and the switching cam gear returns to its original position. be able to.

On the other hand, when the switching cam gear starts rotating and the solenoid is energized just before moving the slider forward, the switching lever swings, and the engaging pin is pushed by the springing means provided on the switching lever, so that the slider is moved forward. As it moves forward, it enters the other side of the guide groove (rewind mode side), and by maintaining the above-mentioned energized state, the switching lever and the cam part of the switching cam gear engage, and the rewind mode can be set. When the power is turned off, all can be returned to their original positions.

In this way, the engagement state between the engagement pin and the guide groove is controlled by the switching lever controlled by the switching cam gear meshing with the drive gear such as the flywheel gear and the switching solenoid, and through the elastic means. Since it is controlled, it has a simple configuration and has the advantage of being able to smoothly switch to fast forward or rewind mode without putting unnecessary load on the switching drive gear.

[Brief explanation of the drawing]

The drawings show an embodiment of the drive gear switching mechanism for a cassette tape recorder according to the present invention, and FIG. The details of the chassis and other parts are omitted to simplify the drawing. Fig. 2 is a plan view showing only the relationship between the drive sources, Fig. 3 is a plan view showing the relationship between the reel stand and the idler, and Fig. 4 is a plan view showing the relationship between the reel stand and the idler.
The figure is a plan view showing the relationship between a drive gear, a control cam gear, a direction arm, and the like. In addition,
1 to 4 all show forward stop conditions. 5A and 5B are perspective views showing the control cam gear, where A is a perspective view as seen from the top side, and FIG. 5B is a perspective view as seen from the bottom side. Figure 6 is a perspective view of the direction arm.
Fig. 7 is a plan view showing the engaged state of the direction arm and the direction slider, Fig. 8 is a rear view showing the head reversing mechanism, and Fig. 9 shows the relationship between the direction slider and the pinch roller. 10 is a rear perspective view of the idler component, FIG. 11 is a plan view showing the fast forward and rewind switching mechanism, and FIGS. 12 to 15 are views of the control cam gear and direction arm. FIG. 12 is a plan view showing the relationship, and FIG. 12 shows the forward stop position.
FIG. 13 shows the reverse stop positions. Fig. 14 is a plan view showing the reversal area of the head from forward to reverse, and Figs. 15 A to F are plan views showing the engagement positional relationship between the control cam gear and the engagement portion (pin) of the direction arm. where A is the forward stop position, B is the forward play position, C is the forward cue position, D is the reverse stop position, E is the reverse play position, and F is the reverse cue position. There is. 16A to 16C are plan views showing the relationship between the control cam gear and the trigger lever, where A shows the stop position for both forward and reverse, B shows the play position for both forward and reverse, and C shows the forward and reverse positions. , shows the positional relationship of reverse queue and review, respectively. 17A to 17D are plan views showing the positional relationship between the idler component and the direction arm,
A indicates the positional relationship between the forward stop and play, B indicates the reverse stop and play position, C indicates the positional relationship between the forward queue and review, and D indicates the positional relationship between the reverse queue and review. There is. FIG. 18 is an operation timing chart of the first solenoid or the second solenoid accompanying each operation. 3... Motor, 5... First solenoid, 6
...Second solenoid as a switching solenoid, 8...Switching lever, 9...Switching drive gear, 14...Idler component, 15...Slide base, 16...Driving gear, 17...Control cam gear , 24... Switching cam gear, 39... Slider, 42... Guide groove, 84... Torsion spring serving as an elastic means, 91... Holding arm, 93... Engaging pin, 241... Pressing cam.

Claims (1)

[Scope of Claim for Utility Model Registration] A switching mechanism for switching a switching drive gear to fast forward or rewind mode, which rotates in mesh with a drive gear such as a flywheel gear by an operating action, and also rotates due to the rotation thereof. The switching cam gear has a cam portion that moves the slider, which is always biased in the backward direction, forward against the biasing force, and an engaging portion that engages with the cam portion formed on the switching cam gear. A switching lever that is swung by a switching solenoid engages with an engagement pin of a holding arm that swings and holds the switching drive gear, and the holding arm is moved to either fast forward or rewind. A bifurcated guide groove is formed on the slider to allow the slider to swing to the above mode, and a bifurcated guide groove is provided on the switching lever to elastically control the engagement of the engagement pin into the guide groove. A drive gear switching mechanism in a tape recorder, characterized in that it is equipped with a triggering means.