JPH0773544A - Operation changeover mechanism in cassette tape recorder or the like - Google Patents

Abstract

PURPOSE:To surely prevent the positional shift on each mode in the state where a mode changeover lever is stopped by making the structure so that the force applied to the mode changeover lever exerts in the direction almost orthogonally crossed with the sliding direction. CONSTITUTION:The mode changeover lever 20, e.g. on the tape running mode in the normal direction, is stopped in the state where line parts 25a, 30a to be pressed of the 1st operating lever 24 and the 2nd operating lever 27 exceed inclined lines of working edge side parts 26a, 31a respectively and come in contact oppositely with an edge part parallel to the sliding direction (a) of the lever 20. Therefore, even though the force is applied to the lever 20 from the sides of levers 24, 27, this force exerts in the directions (b),(c) orthogonally crossed against the sliding direction (a) of the lever 20. As a result, the force does not exert in the sliding direction (a) of the lever 20, thereby the positional shift of the lever 20 is surely prevented. Also, a lock member, etc., for preventing the positional shift of the lever 20 are unrequired, and the number of components is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation switching mechanism in a cassette tape recorder.

[0002]

2. Description of the Related Art At present, various mechanisms having a so-called auto-reverse function are implemented in cassette tape recorders. Usually, a cassette tape recorder having this auto-reverse function is a tape forward drive (forward play, hereinafter referred to as FWD), reverse drive (reverse play, hereinafter referred to as REV), fast forward (fast forward, hereinafter referred to as FF), It has four operation modes of rewinding (hereinafter referred to as REW), and the rotation of the hub drive shaft, the movement of the magnetic head and the pinch roller, etc. can be switched according to each operation mode.

A configuration example of a conventional operation switching mechanism of this type will be briefly described. The operation switching mechanism section has a mode switching lever that is slid by the rotation of the cam gear, and the mode switching lever is stopped at four positions corresponding to the operation modes of FWD, REV, FF, and REW. ing. Further, the operation switching mechanism section has an operating lever which is operated by being pressed by the mode switching lever,
By operating the operating lever in conjunction with the sliding operation of the mode switching lever, the gear transmission path, the rotation ratio, and the rotation speed are changed according to each operation mode to switch the rotation of the hub drive shaft. , The magnetic head and the pinch roller are moved.

[0004]

In such an operation switching mechanism, since the switching operation of gears and the like corresponding to each operation mode is performed by the sliding operation of the mode switching lever, the stop position of the mode switching lever in each operation mode is set. Requires high accuracy. However, in the conventional operation switching mechanism configured as described above, the force applied to the mode switching lever from the operating lever side may cause the mode switching lever to be displaced in the stopped state in each operation mode. In order to prevent this, it is necessary to provide mechanical parts such as a lock lever and a return spring that lock the mode switching lever in each mode. Therefore, in this case, the mechanism becomes complicated, the cost of parts and the number of assembling steps increase, and there is concern about reliability. The present invention has been made for the purpose of improving such problems.

[0005]

In order to achieve the above-mentioned object, the present invention comprises a cam gear that is slid by the rotation of a cam gear.
A mode switching lever that is stopped at a position corresponding to each of the FWD, REV, FF, and REW operating modes, and an operating lever that is pressed and rotated by the mode switching lever to switch gears and the like according to each operating mode. In the mechanism including, in a state where the mode switching lever is stopped in each operation mode, a force applied to the mode switching lever from the operating lever side acts in a direction substantially orthogonal to the sliding direction of the mode switching lever. It is what In the mechanism having the mode switching lever as described above, the cam gear for operating the mode switching lever is provided with a range in which the mode switching lever does not move even if the mode gear is rotated by a certain angle in each mode. The lever may be stopped.

[0006]

In the operation switching mechanism of the present invention configured as described above, even if a force is applied to the mode switching lever from the operating lever side in a state where the mode switching lever is stopped in each mode, this force is used for mode switching. By acting in a direction substantially orthogonal to the sliding direction of the lever, the mode switching lever will not be displaced. In addition, by adopting a structure that stops the mode switching lever within the range in which the mode switching lever does not move even if the cam gear that operates the mode switching lever rotates a certain angle, the mode switching lever can be accurately stopped at the position corresponding to each mode. Therefore, the position shift of the mode switching lever can be more surely prevented, so that a lock lever or the like for locking the mode switching lever becomes unnecessary.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. The embodiment described below describes a case where the present invention is applied to a cassette tape recorder having an auto-reverse function. FIG. 1 shows a tape drive mechanism formed on the back side of a mechanical chassis (hereinafter referred to as a mechanical chassis) 1 of an auto-reverse type cassette tape recorder. 1 and 2
The state shown in (1) is a stopped state which is impossible in the operation of the mechanism according to the embodiment, but is drawn for convenience of explanation.

In the figure, reference numeral 2 is a forward / reverse rotatable motor as a drive source of the mechanism of this example. A belt 6 is stretched around a pulley 2a attached to the rotating shaft of the motor 2, an intermediate pulley 3, and a pair of left and right flywheels 4, 5, that is, by the rotational driving of the motor 2, the left and right flywheels 4 and 5 are driven. Are rotated in opposite directions. The flywheels 4 and 5 are rotated integrally with the FWD capstan and the REV capstan, which are projected to the front surface side of the mechanical chassis 1, respectively.

A gear portion 4a is integrally formed on the lower surface side of one flywheel 4, and a moving gear 7 is meshed with this gear portion 4a. The moving gear 7 is pivotally supported by a tip end portion of a rotating arm 8 which is rotatably mounted with a rotary bearing portion of the flywheel 4 as a fulcrum. Depending on a rotating direction of the flywheel 4, a cam gear 9 and a transmission gear 10 are provided. It is adapted to be selectively meshed.

That is, the moving gear 7 has a first
The small-diameter gear portion 7a and the second small-diameter gear portion 7b having a smaller diameter are integrally formed on the lower surface side of the flywheel 4
1 is rotated clockwise in FIG. 1, the moving gear 7 is swung to the right by the rotational force of the flywheel 4 so that the first small-diameter gear portion 7a meshes with the transmission gear 10, and the flywheel 4 moves. When rotated in the counterclockwise direction, the moving gear 7 is swung to the left, and the second small diameter gear portion 7b is meshed with the cam gear 9. The cam gear 9 is a member that operates a switching mechanism that switches gears, and the cam gear and the switching mechanism will be described later.

A small-diameter gear portion 10a is integrally formed on the lower surface side of the transmission gear 10 with which the moving gear 7 is meshed when the flywheel 4 is rotated clockwise, and the small-diameter gear portion 10a has a transmission gear 11a. Are meshed. Although the configuration of the transmission gear 11 will be described later, the transmission gear 1
A moving gear 12 is meshed with 1.

The moving gear 12 is moved by a switching mechanism to be described later to selectively transmit the rotation to the take-up hub shaft and the supply hub shaft, that is, 13 and 14 are respectively on the front surface side of the mechanical chassis 1. A gear rotated integrally with the projecting winding-side hub shaft and the supply-side hub shaft is shown. A transmission gear 15 is meshed with the gear 13 of the winding-side hub shaft, and the moving gear 12 is leftward in the drawing. When it is moved to the right, it meshes with the transmission gear 15, and when it is moved to the right, it meshes with the gear 14 of the supply side hub shaft.

The structure of the transmission gear 11 described above is shown in FIG.
Further, referring to FIG. 10, the speed change gear 11 has a small-diameter sub gear 11a coaxially rotatable on the lower surface side thereof, and the sub gear 11a is pivotally supported by a pivot 16 which is erected on the mechanical chassis 1 so as to be able to move up and down. . A compression coil spring 17 is inserted between the transmission gear 11 and its sub gear 11a, and the sub gear 11a is rotated together with the transmission gear 11 by the friction of the compression coil spring 17.

The transmission gear 11 is always biased downward by the force of a compression coil spring 19 inserted between a stop washer 18 fitted to the tip of the pivot 16 and a switching mechanism which will be described later. The operation of the mode switching lever causes the compression coil spring 19 to be raised against the biasing force. When the transmission gear 11 is in the lowered position, the sub gear 1 as shown in FIG. 10A.
When the gear 1a meshes with the moving gear 12 and the transmission gear 11 is in the raised position, the main body of the transmission gear 11 meshes with the small-diameter gear portion 12a integrally formed on the upper surface of the moving gear 12 as shown in FIG. The rotation of the transmission gear 11 is transmitted to the moving gear 12 at high speed.

Next, the structure of the switching mechanism for switching the gears and the like will be described. At the center of the mechanical chassis 1,
A mode switching lever 20 for setting four operation modes of FWD, REV, FF, and REW is attached so as to be slidable in a lateral direction (linear sliding). The mode switching lever 20 is slid by the rotation of the cam gear 9, that is, a cam groove 9a having a predetermined shape is continuously formed in the cam gear 9, and the mode switching lever 2 is formed in the cam groove 9a.
The engaging projection 21 provided at the end of 0 is engaged,
The mode switching lever 20 is slid by pressing the engagement protrusion 21 at the inner edge of the cam groove 9a as the cam groove 9a is continuously changed by the rotation of the cam gear 9.

Further, the mode switching lever 20 has an FW
The slide switch 2 is designed to stop at four positions corresponding to the D, REV, FF, and REW modes. The four stop positions of the mode switching lever 20 are detected.
Performed by two. This slide switch 22
It is fixed to a printed wiring board 23 attached to the mechanical chassis 1 so as to cover the drive mechanism part, and its operating element 22a is fixed to an engaging piece 20a standing on the mode switching lever 20. , That is, mode switching lever 2
The operator 22a of the slide switch 22 is moved along with the sliding operation of 0, and the position of the mode switching lever 20 is detected.

The mode switching lever 20 is adapted to rotate the first operating lever 24 and the second operating lever 27 by the sliding operation thereof. The rotation of the first operating lever 24 causes the hub drive shaft to rotate. The operation of switching the transmission path of the gear to is performed, and the rotation of the second actuating lever 27 causes the magnetic head and pinch roller (neither shown in the figure) provided on the front side of the mechanical chassis 1. The moving operation is performed.

First, the first actuating lever 24 will be described. The first actuating lever 24 is rotatably mounted coaxially with the pivot 16 of the transmission gear 11, and the above-described first actuating lever 24 is mounted on the first actuating lever 24. A moving gear 12 is pivotally supported. The first actuating lever 24 has a pair of pressed edge portions 2
5a and 25b are symmetrically provided, and the pressed edge portions 25a and 25b are attached to the mode switching lever 20 so as to be in contact therewith.
Action edge portions 26a, 26 having inclined edges for pressing
b is formed symmetrically.

As the mode switching lever 20 slides, the action edge portion 26a or 26b pushes the pressed edge portion 25a or 25b of the first operating lever 24 so that the first operating lever 24 is pivoted. In the direction in which the moving gear 12 pivotally supported on the first actuating lever 24 meshes with the transmission gear 15 on the take-up hub shaft side or the gear 14 on the supply hub shaft. Moved selectively.

On the other hand, the second operating lever 27 is attached to the mechanical chassis 1 so as to be movable around a pivot 28 as a fulcrum, and the second operating lever 27 is pressed against the central portion and both left and right ends thereof. Pieces 27a, 27b, 27c are provided, and these pressing pieces 27a, 27b, 27c project to the front surface side of the mechanical chassis 1 through the through holes 29 and correspond to the magnetic head, the FWD pinch roller, and the REV pinch roller, respectively. ing.

The second actuating lever 27 is provided with a pair of pressed edge portions 30a and 30b symmetrically, and the mode switch lever 20 is opposed to the pair of pressed edge portions 30a and 30b.
Working edge portion 3 having inclined edges for pressing a and 30b respectively
1a and 31b are formed symmetrically, and the action edge portion 31a is formed by the sliding operation of the mode switching lever 20.
Alternatively, 31b is the pressed edge portion 30 of the second actuating lever 27.
By pressing a or 30b, the second actuating lever 27 rotates about the pivot 28 as a fulcrum, whereby the pressing piece 27a at the center presses the magnetic head to move it, and at the same time the pressing pieces 27b at both ends are moved. Or 27c is FWD
The pinch roller for REV or the pinch roller for REV is selectively pressed and moved.

Further, as is apparent from FIG. 9, the mode switching lever 20 is provided with a conical taper projection 32 at a position corresponding to the lower side of the transmission gear 11 by a drawing process of a sheet metal. A receiving convex portion 33 is provided on the lower surface side of the sub gear 11a of the transmission gear 11. Then, as the mode switching lever 20 slides, the tapered projection 32 comes into contact with the receiving projection 33, so that the speed change gear 11 rises from the lowered position integrally with the sub gear 11a against the force of the compression coil spring 19. The structure is made.

Next, the operation of the mechanism configured as described above will be described. First, in the cassette tape recorder of this example, the FWD, REV, and F
Even if either the F or REW operation button is pressed,
First, the motor 2 is rotationally driven in the opposite direction (counterclockwise in FIG. 1).

When the motor 2 is thus rotated in the opposite direction, the flywheel 4 is rotated in the counterclockwise direction, so that the moving gear 7 is swung to the left and the second small diameter gear portion 7b meshes with the cam gear 9. That is, the rotational force of the motor 2 is transmitted in the order of the motor 2 → belt 6 → flywheel 4 → moving gear 7 → cam gear 9 to rotate the cam gear 9. The rotation of the cam gear 9 causes the mode switching lever 20 to slide, so that the FWD, REV, and
Either FF or REW mode is set.

When the slide switch 22 detects that the mode switching lever 20 has moved to the position of the mode corresponding to the operation button pressed by the operation section, the printed wiring board is detected based on the detection signal from the slide switch 22. 23, the rotation direction of the motor 2 is immediately reversed in the forward direction (clockwise in FIG. 1) by a controller (not shown), and as a result, the moving gear 7 is swung to the right and meshes with the transmission gear 10. To be done. Therefore, at this time, the rotation of the cam gear 9 stops, and therefore the mode switching lever 20 is stopped at the position corresponding to each mode.

The state of each mode set by the mode switching lever 20 will be described. First, the FW shown in FIG.
In the D mode, the mode switching lever 20 is in the slide position closest to the left end, and in this state, the pressed edge portion 25a of the first operating lever 24 is pressed by the inclined edge of the action edge portion 26a of the mode switching lever 20. As a result, the first actuating lever 24 tilts to the left around the pivot 16 as a fulcrum, so that the moving gear 12 meshes with the transmission gear 15 on the take-up side hub shaft side. At the same time, the inclined edge of the working edge portion 31a of the mode switching lever 20 causes the second operating lever 2 to move.
The pressed edge portion 30a of the second operation lever 2 is pressed.
7 tilts to the left symmetrically with the first actuating lever 24 about a pivot 28 as a fulcrum, whereby the pressing piece 27a at the center presses the magnetic head in the direction of pressing the magnetic head against the tape of the tape cassette and the pressing of the left end. The piece 27b presses the pinch roller for FWD in the direction in which the pinch roller for FWD is pressed against the capstan for FWD. Further, in the FWD mode, the taper protrusion 32 of the mode switching lever 20 is the sub gear 1 of the transmission gear 11.
1a is in a position not corresponding to the receiving convex portion 33 of the gear 1a, so that the transmission gear 11 is integrally formed with the sub gear 11a.
Is held in the lowered position as shown in FIG. 10A.

Further, in the REV mode shown in FIG.
Symmetrically to the above FWD mode, the mode switching lever 20
Is in the slide position closest to the right end, and in this state, the pressed edge portion 25b of the first operating lever 24 is pressed by the inclined edge of the operating edge portion 26b of the mode switching lever 20 so that the first operating lever 24 moves. It tilts to the right with the pivot 16 as the fulcrum, so that the moving gear 12 is the gear 1 of the supply side hub shaft.
4 is meshed. At the same time, the mode switching lever 2
The pressed edge portion 30b of the second actuating lever 27 is pushed by the inclined edge of the action edge portion 31b of 0, so that the second actuating lever 27 moves symmetrically to the right with respect to the first actuating lever 24 with the pivot 28 as the fulcrum. Tilted to the center, which causes the pressing piece 27 in the central portion.
The a presses the magnetic head in the direction of pressing the tape of the tape cassette, and the pressing piece 27c at the right end presses the pinch roller of the REV in the direction of pressing the capstan for the REV. Also in this REV mode, as in the FWD mode, the taper projection 32 of the mode switching lever 20 is in a position not corresponding to the receiving projection 33 of the sub gear 11a of the transmission gear 11, and therefore the transmission gear 11 is integrally compressed with the sub gear 11a. It is held in the lowered position by the force of the coil spring 19 as shown in FIG. 10A.

In the FF mode shown in FIG. 5, the mode switching lever 20 is in the sliding position to the left of the neutral position. In this state, the first actuating lever is moved by the inclined edge of the working edge portion 26a of the mode switching lever 20. The pressed edge portion 25a of 24 is pressed, and the first actuating lever 24 tilts to the left with the pivot 16 as the fulcrum.
2 is meshed with the transmission gear 15 on the take-up side hub shaft side. still,
In this FF mode, as is apparent in the figure, one action edge 31a of the mode switching lever 20 and the second operating lever 2
The pressed edge portion 30 a of the second actuating lever 27 is in contact with the pressed edge portion 30 a of the second working lever 27 in a state where the working edge 31 a does not press the pressed edge portion 30 a of the second actuating lever 27. At the same time, a predetermined gap is set between the other operating edge 31b of the mode switching lever 20 and the other pressed edge 30b of the second operating lever 27. As a result, since the second actuating lever 27 is not rotated, the moving operation of the magnetic head and the pinch roller is not performed.
Further, in the FF mode, the taper projection 32 of the mode switching lever 20 abuts and engages with the receiving convex portion 33 of the sub gear 11a of the transmission gear 11, so that the transmission gear 11 is integrated with the sub gear 11a by the force of the compression coil spring 19. Against Figure 10
As shown in B, it is in the raised position.

In the REW mode shown in FIG. 6,
In contrast to the FF mode, the mode switching lever 20 is in the sliding position to the right of the neutral position, and in this state, the inclined edge of the working edge portion 26b of the mode switching lever 20 causes the pressed edge portion of the first operating lever 24 to move. 25b is pressed and the first actuating lever 24 tilts to the right with the pivot 16 as the fulcrum, so that the moving gear 12 moves to the gear 14 of the supply side hub shaft.
Meshed with. In this REW mode, as is apparent from the figure, one action edge 31a of the mode switching lever 20 is
A predetermined gap is formed between and the one pressed edge portion 30a of the second actuating lever 27. At the same time, the other operating edge 31b of the mode switching lever 20 and the second operating lever 2
The other edge 7b to be pressed of 7 is in contact with the action edge 31b without pressing the edge 30b to be pressed. As a result, as in the FF mode, since the second actuating lever 27 is not rotated, the magnetic head and the pinch roller are not moved. Also in this REW mode, as in the FF mode, the taper protrusion 32 of the mode switching lever 20 is used.
Engages with the receiving projection 33 of the sub gear 11a of the speed change gear 11, so that the speed change gear 11 is integrated with the sub gear 11a to the position raised as shown in FIG. 10B against the force of the compression coil spring 19. is there.

Then, as described above, the mode switching lever 20
FWD, REV, FF, REW depending on the slide position of
With each mode set, the mode switching lever 2
The structure is such that no displacement occurs at 0.

That is, in the FWD mode, for example, as apparent from FIG. 3, the mode switching lever 20 has the pressed edge portions 25 of the first operating lever 24 and the second operating lever 27.
a and 30a are stopped in a state of touching the edges parallel to the sliding direction of the mode switching lever 20 beyond the inclined edges of the action edge portions 26a and 31a, respectively.
Therefore, the first operating lever 24 and the second operating lever 2
Even if a force is applied to the mode switching lever 20 from the 7 side, this force acts in a direction (directions of arrows b and c) orthogonal to the sliding direction of the mode switching lever 20 (direction of arrow a in FIG. 3), and therefore the mode is changed. Since the force in the sliding direction does not act on the switching lever 20, the mode switching lever 20 does not slide unexpectedly.

The cam gear 9 used in this mechanism is
The cam groove 9a has a shape as shown in FIG. 7. When the stroke of the mode switching lever 20 slid in the cam groove 9a is taken as the ordinate and the rotation angle of the cam gear 9 is taken as the abscissa, FIG. As shown. As is clear from this, the cam groove 9a has a range in which the mode switching lever 20 does not move even if the cam gear rotates a certain angle in each mode. In the mechanism of this example, the rotation of the cam gear 9 is stopped within this range. The switching lever 20 is stopped.

By doing so, it becomes easy to accurately stop the mode switching lever 20 at the position corresponding to each mode, and even if some force is applied to the cam gear 9 from the mode switching lever 20 side, the cam gear 9 Since 9 is not rotated, the mode switching lever 20 does not unexpectedly slide, and therefore the position shift of the mode switching lever 20 can be more reliably prevented.

By thus stopping the mode switching lever 20 in each mode without causing displacement, the state of the switching mechanism in each mode is stably maintained.

After each mode is set by the rotation of the cam gear 9 as described above, the motor 2 is operated as described above.
When the moving gear 7 separates from the cam gear 9 and meshes with the transmission gear 10 due to the normal rotation of 1, the hub drive shaft corresponding to each mode is rotationally driven.

That is, in the FWD mode and the FF mode, the rotational force of the motor 2 is the motor 2 → belt 6 → flywheel 4 → moving gear 7 → transmission gear 10 → shift gear 1
1 → Moveable gear 12 → Transmission gear 15 → Gear 13 of the winding side hub shaft is transmitted to rotate the winding side hub shaft. In this case, in the FWD mode, the transmission gear 11 is in the lowered position as shown in FIG. 10A, and the sub gear 11a meshes with the moving gear 12, while in the FF mode, the transmission gear 11 is in the lowered position.
Is engaged with the small-diameter gear 12a of the moving gear 12 at the raised position shown in FIG. 10B, the winding-side hub shaft is rotated at a higher speed in the FF mode than in the FWD mode due to the difference in gear ratio between the two.

In the REV mode and the REW mode, the rotational force of the motor 2 is the motor 2 → the belt 6 →
The supply hub shaft is rotated by being transmitted as flywheel 4 → moving gear 7 → transmission gear 10 → transmission gear 11 → moving gear 12 → gear 14 of the supply side hub shaft. In this case, in the REV mode, the transmission gear 11 is in the lowered position as shown in FIG. 10A and the sub gear 11a meshes with the moving gear 12, while in the REW mode, the transmission gear 11 is shown in FIG.
The small-diameter gear 12 of the moving gear 12 in the raised position shown in B
Since it meshes with a, the supply-side hub shaft is rotated at a higher speed in the REW mode than in the REV mode due to the difference in gear ratio between the two.

The drive mechanism of the cassette tape recorder of the present example configured and operated as described above is devised so as to prevent the mode switching lever 20 from being displaced in each mode. In addition, there is no need for mechanical parts such as lock levers and return springs to prevent the position shift of the mode switching lever, so the number of parts can be kept small and the cost of parts and assembly man-hours can be reduced, and the mechanism is simple. Therefore, the failure rate is low and it is effective in terms of reliability.

Further, in the mechanism of this embodiment, the taper projection 32 provided on the mode switching lever 20 is configured to perform the up-and-down operation of the shift gear 11, that is, the shift switching operation, in conjunction with the sliding operation of the mode switching lever 20. Therefore, since it is not necessary to provide a special mechanism for moving the transmission gear 11 up and down, the structure becomes simpler, and therefore the cost of parts and the number of steps can be further reduced.

Although the embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the configuration of this embodiment and can take various forms.

[0041]

As is apparent from the above description, the invention according to claim 1 of the present invention is slid by the rotation of the cam gear and stopped at a position corresponding to each operation mode of FWD, REV, FF and REW. And a mode switching lever that is pressed and rotated by the mode switching lever,
In a mechanism including an operating lever that switches gears and the like according to each of the above operation modes, when the mode switching lever is stopped in each operation mode, the force applied from the operation lever side to this mode switching lever is By adopting a structure that operates in a direction substantially orthogonal to the sliding direction of the mode switching lever, it is possible to reliably prevent the position shift of the mode switching lever in each mode.

According to a second aspect of the present invention, the cam gear is slid by the rotation of the cam gear and the FWD,
In a mechanism having a mode switching lever that stops at a position corresponding to each of the REV, FF, and REW operation modes, and switches gears and the like according to the mode, the cam gear rotates in the above-mentioned operation modes by an angle. However, there is a range in which the mode switching lever does not move, and by adopting a structure in which the mode switching lever is stopped within this range, it is possible to more reliably prevent displacement of the mode switching lever in each mode.

Since the position shift of the mode switching lever does not occur in this way, it is not necessary to provide a mechanical component such as a lock lever for preventing the position shift of the mode switching lever as in the conventional case, and therefore the number of components is increased. It is possible to reduce the parts cost and the assembly man-hour,
Also, since the mechanism is simple, it is highly effective in terms of reliability.

Further, in the invention described in claim 3 of the present invention, the FW is slid by the rotation of the cam gear.
A mode switching lever for switching gears and the like according to each operation mode of D, REV, FF, REW, and FWD, REV
And a shift gear that changes the rotation speed transmitted to the hub drive shaft by moving up and down in the mode and the FF and REW modes, and this shift gear is interlocked with the sliding operation of the mode switch lever by the protrusion formed on the mode switch lever. Since it has a structure that can be moved up and down, there is no need to install a special mechanism for raising and lowering the transmission gear, which simplifies the configuration, further reduces parts cost and man-hours, and realizes a cheaper cassette tape recorder. It is a great contribution.

[Brief description of drawings]

FIG. 1 is a plan view of a drive mechanism portion of a cassette tape recorder showing an embodiment.

FIG. 2 is a plan view of a switching mechanism section.

FIG. 3 shows an operating state (FWD mode) of a switching mechanism section.

FIG. 4 shows an operating state (REV mode) of the switching mechanism section.

FIG. 5 shows an operating state (FF mode) of the switching mechanism section.

FIG. 6 shows an operating state (REW mode) of the switching mechanism section.

FIG. 7 is an explanatory diagram of a cam gear.

FIG. 8 is a graph illustrating a cam groove shape of a cam gear.

FIG. 9 is a vertical cross-sectional side view showing the structure of a transmission gear.

10A and 10B are explanatory views of the up-and-down movement of the transmission gear, in which A is in the lowered position and B is in the raised position.

[Explanation of symbols]

 2 Motor 9 Cam gear 11 Speed change gear 12 Moving gear 13 Winding side hub shaft gear 14 Supply side hub shaft gear 20 Mode switching lever 24 First operating lever 27 Second operating lever 32 Tapered protrusion

Claims (3)

[Claims] 1. A slide is provided by rotation of a cam gear,
Forward running (FWD), reverse running (REV) of tape,
A mode switching lever that is stopped at a position corresponding to each of the fast-forward (FF) and rewind (REW) operation modes, and is rotated by being pressed by the mode switching lever to switch gears and the like according to each of the above-mentioned operation modes. In a state in which the mode switching lever is stopped in each of the operation modes, the force applied from the operating lever side to the mode switching lever is in the sliding direction of the mode switching lever. An operation switching mechanism for a cassette tape recorder or the like, which has a structure that works in a direction substantially orthogonal to each other. 2. The tape is slid by the rotation of a cam gear, and the tape runs in the forward direction (FWD) and runs in the reverse direction (R).
In a mechanism having a mode switching lever that stops at a position corresponding to each operation mode of EV), fast forward (FF), and rewind (REW), and switches the gears according to the mode, the cam gear is There is a range in which the mode switching lever does not move even if the operation mode is rotated by an angle,
An operation switching mechanism for a cassette tape recorder or the like, which has a structure for stopping the mode switching lever within this range. 3. Sliding by rotation of a cam gear,
Forward running (FWD), reverse running (REV) of tape,
A mode switching lever that switches gears and the like according to each operation mode of fast forward (FF) and rewind (REW), and forward running (FWD), reverse running (REV) mode and fast forward (FF) of tape, winding. It goes up and down with the return (REW) mode,
And a shift gear that changes the rotational speed transmitted to the hub drive shaft, and the shift gear is configured to move up and down in conjunction with the sliding operation of the mode switch lever by a protrusion formed on the mode switch lever. The operation switching mechanism for the featured cassette tape recorders.