JP2000200452A - Gear changeover device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to well mesh the gears of a gear change device with each other when a gear changeover device is shifted to a state of meshing the gears with each other. SOLUTION: The shaft barrel part 100 of the one gear 80 is pivotally supported by forked spindle part 84 and sub-shaft part 92 of a shaft member 78. When the meshing of the gears 80 and 120 with each other is defective, the end peripheral part 102 of the shaft barrel part 100 is disengaged from a positioning part 96 of a head part 92 of the sub-shaft part 86 and the end peripheral part 102 manipulates an inclined guide part to deflect the sub-shaft part 86. The shaft barrel part 100 of the one gear 80 is then elastically deformed in an inclined state with respect to the revolving shaft of the shaft member 78. As a result, the frictional resistance in the portions where the gears are meshed with each other is reduced and the gears are turned with each other in different directions with relatively small torque so that the gear can reset to the state of meshing each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear switching device suitable for use in a gear mechanism or the like capable of changing a tape recorder, for example, to drive a tape winding shaft at a high speed or at a normal speed. .

[0002]

2. Description of the Related Art Electrical equipment using a conventional gear mechanism includes:
For example, there is a cassette recorder as a tape recorder that mechanically operates the operation states of various mechanisms including switching of a tape winding speed by selectively operating a plurality of push button devices.

In such a cassette recorder, FIG. 9 is attached to a part of a gear mechanism for allowing a tape to run at a high speed during fast-forward and rewind, and to allow the tape to run at a normal speed during a recording or reproducing operation. As an example, a gear switching device has been proposed.

[0004] The illustrated gear switching device includes an engaged state of a combination of a high-speed side gear and an engaged state of a normal-speed side gear by moving a driving side gear member 12 in an axial direction with respect to a driven side gear member 10. And a switching operation.

The driven gear member 10 is rotatably and non-tiltably mounted on a shaft member 16 provided integrally with the mechanical chassis 14. The shaft member 16 is configured so that the driven gear member 10 can be mounted with one touch. For this reason, the shaft member 16 forms a conical surface portion at the base end of the shaft portion, and forms a shaft rod extending toward the distal end side thereof into a substantially D-shaped flat cross section. Further, a sub-shaft portion 18 having a hook head 18B formed with a contact flat portion 18A which is elastically deformable and extends at a right angle to the distal end is extended to a portion where the round shaft of the shaft is cut off. It is configured to be.

The driven side gear member 10 is provided with a shaft cylinder 20.
A conical inner peripheral surface is formed in a part of the outer peripheral portion, and a small-diameter gear 22 for high-speed rotation, a large-diameter gear 24 for normal-speed rotation, and a lower gear 22 And an output gear 26 having a small diameter.

The driven gear member 10 constructed as described above
Is pushed from the large-diameter opening side of the shaft cylinder portion 20 on the output gear 26 side so as to pass the tip of the shaft member 16,
It advances while bending the sub shaft portion 18 along the conical inner peripheral surface of the shaft tube portion 20. When the large-diameter opening end periphery of the shaft cylinder portion 20 hits the plane of the mechanical chassis 14, the hook head 18B
Is disengaged from the inner peripheral surface of the shaft cylinder portion 20 and elastically returns in the radial direction by its own elastic restoring force.
FIG. 9 shows a state in which A is brought into contact with the peripheral portion of the opening end of the shaft cylinder portion 20 on the side of the small-diameter gear 22 for high-speed rotation.

In this mounted state, the shaft cylinder portion 20 is
6 and is supported so as to be immovable in the axial direction such that both open end peripheral portions of the shaft cylinder portion 20 are sandwiched between the plane of the mechanical chassis 14 and the contact flat portion 18A. Therefore, the driven gear member 10 is freely rotatable around the axis of the shaft member 16 which is firmly integrated and fixed to the mechanical chassis 14, and the driven gear member 10 is rotated with respect to the axis of the shaft member 16. It is firmly supported so that the rotation axis does not tilt.

The drive side gear member 12 has a shaft cylinder 28
Is mounted on a shaft member 30 provided on the mechanical chassis 14 so as to be freely rotatable around the axis and movable in the axial direction.
A small drive gear 32 meshable with the large-diameter gear 24 is attached to the mechanical chassis 14 side of the shaft cylinder 28 so as to rotate integrally. Further, a large sliding drive gear 36 is mounted so as to transmit a rotational torque of a certain level or less to a side surface of a flange portion 34 formed integrally with the shaft cylinder portion 28 through a sliding interlocking member 35 made of felt. Have been. The large sliding drive gear 36 is configured to be able to mesh with the small diameter gear 22 of the driven gear member 10.

The drive side gear member 12 includes a shaft member 3.
0 between the cover 30A and the shaft cylinder 28.
8 is urged to move to the mechanical chassis 14 side. Further, a compression coil spring 40 is arranged between the shaft cylinder portion 28 and the large sliding drive gear 36, and a sliding interlocking member 35 is sandwiched between the large sliding drive gear 36 and the flange portion 34 so that By generating a constant frictional force during the rotation, a rotational torque up to a predetermined value can be transmitted.

The drive-side gear member 12 constructed as described above
Is set at a predetermined position on the mechanical chassis 14 side so that the large-diameter drive gear 36 engages with the small-diameter gear 22 in order to rotate the tape winding shaft interlocked with the output gear 26 at a high speed during a fast-forward or rewind operation. It is set in a state where it is moved by the urging force of the spring 38. Further, the drive side gear member 12
At the time of the play operation, the play lever 42 is inserted between the mechanical chassis 14 and the shaft cylinder 28, and the drive gear member 12 is moved so as to be separated from the mechanical chassis 14, and the tape winding shaft is moved. The small drive gear 32 is set to mesh with the large diameter gear 24 so as to rotate at a normal speed.

[0012]

In the gear switching device as described above, the high-speed driving state of fast-forwarding or rewinding is used.
When switching to the driving state at the normal speed during the play operation, the teeth of the large-diameter gear 24, which did not mesh well with the teeth of the small drive gear 32, may ride up, resulting in a poor meshing state as illustrated in FIG. .

This is because the drive side gear member 12 is moved along the axis of the shaft member 30 by the play bar 42 so that
When moved away from 4, the teeth of the small drive gear 32 hit the teeth of the large diameter gear 24. At this time, it suffices if either of the teeth moves a little, etc., so that both teeth can be engaged.
In the case of a position in which no engagement can be made, the small drive gear 32
The drive-side gear member 12 advances to the position shown in FIG.

The operation of moving the driving side gear member 12 is performed with a strong force, and the driven side gear member 10 cannot tilt with respect to the shaft member 16, so as shown in FIG.
Will be greatly bent and deformed.

Therefore, the teeth of the large-diameter gear 24 are strongly pressed onto the teeth of the small drive gear 32 with a strong force enough to largely deform the large-diameter gear 24, and a large frictional force acts between the two. State.

In the state shown in FIG. 9, when the power, which is the driving source of the gear mechanism, is turned on and driven, the driving force of this motor is transmitted to the large driving gear 36. However, when the driving force transmitted to the large sliding drive gear 36 is transmitted to the flange portion 34 via the sliding interlocking member 35, the driving force is limitedly transmitted so as not to exceed a predetermined value of torque. Therefore, the braking force that stops the rotation of the small drive gear 32 because the teeth of the large-diameter gear 24 ride on the teeth of the small drive gear 32 so that the teeth of the large-diameter gear 24 are strongly pressed against the teeth of the large drive gear 3
When the torque is larger than a predetermined value transmitted from the motor 6 to the small drive gear 32 via the slide interlocking member 35, the large slide drive gear 36 idles and the large diameter gear 24 is placed on the small drive gear 32 shown in FIG. The poor meshing state that the vehicle rides is maintained.

In the case of such a poor meshing state, there is a problem that the large-diameter gear 32 is deformed or the teeth on the riding portion are damaged, which causes a failure.

In view of the above facts, the present invention provides a new gear switching device that can be meshed well when shifting from a state in which the gears are separated from each other to be disengaged so as to mesh with each other. The purpose is to provide.

[0019]

According to a first aspect of the present invention, there is provided a gear switching device comprising: a first gear and a second gear which can be meshed or separated by relatively moving; and a first gear. A shaft member in which the main shaft portion and the sub shaft portion are axially inserted into the shaft hole of the shaft tube portion, and a head provided so as to project from the tip of the sub shaft portion faces one end peripheral portion of the shaft hole in the shaft tube portion. In the gear switching device configured as described above, a predetermined shaft support position is held at the head of the countershaft portion in contact with the end peripheral portion of the shaft cylinder portion when the first gear is in a normal rotation state. The positioning section is formed, and the inclined guide section is formed on the slope following the positioning section. When the first gear is urged in the moving direction by the movement of the second gear, the end peripheral portion of the first gear is moved. The first gear is inclined with respect to the shaft member by elastically bending the sub shaft portion by sliding while pressing the inclined guide portion. Characterized by being configured.

With the above configuration, the first,
The head of the auxiliary shaft portion of the shaft member that supports the shaft cylinder portion of the first gear when a poor meshing occurs when the second gear shifts from the disengaged state to the meshed state. The end peripheral portion of the shaft cylinder portion is disengaged from the positioning portion provided on the shaft member, and by pressing the inclined guide portion, the sub shaft portion is flexed, and the shaft cylinder of the first gear with respect to the rotation axis of the shaft member. The part is elastically displaced in a state of being inclined. As a result, the frictional resistance of the portion where the gears are in contact with each other due to poor meshing is reduced, and when the gears in the poorly meshed state are rotated with relatively small torque in relatively different directions, the The teeth mesh with each other, and the first gear resiliently returns to a state where the first gear is concentric with the shaft member, thereby enabling transition to a proper meshing state.

According to a second aspect of the present invention, in the gear switching device according to the first aspect, when the shaft cylinder portion of the first gear is moved to the inclined state with respect to the shaft member, the first gear is hooked on the end peripheral portion. In order to prevent the head from coming off, a reversing structure is provided to protrude from the free end side of the head in the base end direction of the countershaft to serve as a stopper.

With the above-described structure, even when the first gear is moved so as to be inclined with respect to the shaft member, the structure is engaged with the end peripheral portion so as to prevent the first gear from falling off the shaft member. Stop and ensure the operation of shifting to the meshing operation.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a gear switching device according to the present invention will be described with reference to FIGS. FIG. 6 is a plan view schematically showing a main part of a cassette recorder provided with the gear switching device according to the present embodiment.

The cassette recorder as a whole is provided inside a substantially rectangular box-shaped housing having an open upper flat portion.
A printed circuit board is placed on top of which a mechanical chassis as a support member is integrated with the housing and integrated with the center frame that constitutes the case body, and a gear mechanism with a gear switching device is mounted. , And a lid is attached to the center frame so as to be openable and closable.

As shown in FIG. 6, the cassette recorder body 5
0 so that a part thereof protrudes from the side 52 of the
4. A play button 56, a rewind button 58, and a stop button 60 are mounted on the mechanical chassis 62.

The cassette recorder body 50 described above
In this configuration, any one of the fast forward button 54, the play button 56, and the rewind button 58 can be set to a pressing operation state. By pressing the stop button 60, each of the buttons 54, 56 or 58
Is returned to the standby position.

Further, when any one of the fast forward button 54, the play button 56, and the rewind button 58 is pushed to the operating position, and the other button 54, 56, or 58 is pushed, the operating position is changed to the operating position. Button 5
4, 56 or 58 is configured to be returned to the standby position.

On the mechanical chassis 62, first and second reel shafts 64 and 66 for rotating and driving respective hubs of a cassette tape (not shown) are rotatably mounted. Reel gears 68 and 70 are provided on the first and second reel shafts 64 and 66, respectively, so as to rotate integrally. An idle gear 72 for reversing the rotation direction is provided on the reel gear 68 of the first reel shaft. It is attached to the chassis in a meshed state.

Between the reel gear 70 of the second reel shaft 66 and the idle gear 72, a switching lever member 74 and a connection gear 76 for constituting a traveling direction switching mechanism are mounted.

The switching lever member 74 is made of a synthetic resin and is formed in a flat plate having a predetermined shape, and a predetermined position at an intermediate portion thereof is axially attached to the mechanical chassis 62 by a shaft member 78. Further, on the switching lever member 74, a driven gear member 80 composed of three gears constituting a part of a gear switching device is coaxially mounted on the shaft member 78 coaxially. At the same time, at one end of the switching lever member 74 facing the first and second reel shafts 64 and 66, a connection gear 76 meshing with the output gear of the driven gear member 80 is mounted. .

In this traveling direction switching mechanism, the switching lever member 7 is operated in conjunction with the operation of a fast forward button 54, a rewind button 58, or a knob mechanism (not shown) for switching the traveling direction.
4 is rotated around the shaft member 78 in the direction of arrow A or B to selectively mesh the connection gear 76 with the idle gear 72 on the first reel shaft 64 or the reel gear 70 on the second reel shaft 66. An operation of switching the traveling direction is performed.

As shown in FIG. 6, a gear switching device for selectively switching and transmitting a high-speed rotation driving force or a normal-speed rotation driving force to the traveling direction switching mechanism described above includes a switching lever member 74 having a shaft. By moving the drive side gear member 82 in the axial direction with respect to the driven side gear member 80 coaxially mounted on the shaft member 78 to be mounted, the meshing state of the high speed side gear and the normal speed side gear combination can be changed. The switching operation can be performed as the meshing state.

As shown in FIGS. 1, 7 and 8, the driven gear member 80 is rotatably tilted by a pivot shaft member 78 provided integrally with the mechanical chassis 62 and elastically inclined by an external force exceeding a certain level. It is possible and is mounted so that it can return when external force is removed. The shaft member 78 is configured so that the driven gear member 80 can be mounted with one touch.

As shown in FIG. 1, FIG. 7 and FIG.
Numeral 8 is formed integrally with a plastic mechanical chassis 62 by injection molding, the base end of which is formed to have a substantially D-shaped cross section and a thick shaft, and a tapered conical surface portion in the middle. The main shaft portion 84 and the sub shaft portion 86 are formed such that the main shaft portion 84 and the sub shaft portion 86 are bifurcated from the middle portion to the front end.

Further, around the base end of the shaft member 78,
An auxiliary shaft portion 88 as a part of the shaft member 78 is formed integrally with the mechanical chassis 62 so as to protrude in a ring shape and has an outer peripheral surface formed on a circumferential surface concentric with the shaft rod of the shaft member 78. ing. The shaft cylinder portion 100 of the driven gear member 80 is mounted on the main shaft portion 84 and the sub shaft portion 86 of the shaft member 78, and the switching lever member 7 described above is mounted on the auxiliary shaft portion 88.
4 is mounted on the shaft.

As shown in FIGS. 1, 2, 7 and 8, the main shaft portion 84 of the shaft member 78 is formed so that its transverse cross section has a shape in which a concave portion 90 is provided by cutting out a part of an arc. I have. Further, the shaft member 78 is provided with a sub shaft portion 86 at a portion corresponding to the concave portion 90 of the main shaft portion 84. This counter shaft 86
Are formed in a substantially rectangular small piece shape, and the base end thereof is
8 is integrally connected to the intermediate portion. This counter shaft 86
A head 92 formed so as to have a substantially tapered trapezoidal shape when viewed from the side is integrally formed at an end portion of the front end with an outward direction opposite to the main shaft portion 84.

As shown in FIGS. 2, 3 and 4, the head 9
A positioning portion 94, an inclined guide portion 96, and a reversing structure portion 98 are continuously and integrally formed on the bottom surface of the concave portion on the base end side of No. 2. The inclined guide section 96 is provided with the counter shaft section 8.
6 is formed as a sloped portion (in this specification, a curved surface is included in the present specification) so as to enter a predetermined length from the outer side surface 86A to the outside of the distal end of the head portion 92.

The configuration of the inclination guide portion 96 such as the gradient and length is determined when the end peripheral portion 102 of the shaft cylinder portion (boss) 100 pushes the inclination guide portion 96 along the axial direction of the shaft member 78. The sub shaft portion 86 is slidably contacted with the inclined guide portion 96.
Is set to be sufficiently bent.

Further, the positioning portion 94 is provided on the outer surface 86A.
Is formed as a ridge angle which can be a boundary between the inclined guide portion 96 and a slope (in this specification, the meaning of a curved surface is included).

The inclined guide portion 96 may be formed as a concave curved surface as shown in FIG. 5, or may be formed as a convex curved surface (not shown). Also in this case, the positioning portion 94 is set at the boundary between the outer surface 86A and the curved surface of the inclined guide portion 96.

Further, as shown in FIG. 5, even when the boundary between the outer surface 86A and the curved surface of the inclined guide portion 96 is relatively smoothly continuous, the end peripheral portion 102 of the shaft cylinder portion 100 slidingly contacting the outer surface 86A is positioned. If the user tries to move from the 94 to the inclined guide part 96 side, the sub shaft part 86 is bent, so that the repulsive force acts to return the shaft cylinder part 100 to the position of the positioning part 94. The positioning section 94
Any configuration may be used as long as the end peripheral portion 102 of the shaft cylinder portion 100 provides a required resistance when moving from the outer surface 86A to the inclined guide portion 96 side.

As shown in FIG. 2, FIG. 3, and FIG.
The warp structure portion 98 of the head portion 92 of the sixth portion extends the side surface portion of the head portion 92 away from the outer side surface 86A toward the base end side of the sub shaft portion 86, and the end peripheral portion 102 of the shaft cylinder portion 100.
Is formed so as not to come off. Note that, in the structure shown in FIG. 5, the opposite structure portion 98 is similarly formed.

Further, in order to properly lock the end peripheral portion 102 of the shaft cylinder portion 100 with the reversing structure 98 of the head portion 92, a shaft hole on the head portion 92 side of the shaft cylinder portion 100 is provided. A stepped portion 104 is formed in the peripheral portion of the mouth end by leaving a portion of the end peripheral portion 102 close to the inner periphery of the shaft hole in a ring shape and cutting off the outer peripheral side portion.

By forming in this manner, as shown in FIG. 4, the tip of the warped structure 98 faces the step 104,
The warpage structure 98 and the end peripheral portion 102 are hooked and locked to each other, and are supported so that the shaft cylinder 100 does not come off the head 92.

As shown in FIGS. 1, 7 and 8, the driven gear member 80 has a conical inner peripheral surface formed in a part of the shaft cylinder portion 100 and a high-speed A small-diameter gear 106 for rotation, a large-diameter gear 108 for normal-speed rotation below the lower gear, and a small-diameter output gear 110 below the lower gear are integrally formed.

The driven gear member 80 thus configured
When the front end of the shaft member 78 is pushed through the large-diameter opening of the shaft cylinder portion 100 on the output gear 110 side, the sub shaft portion 86 is moved along the conical inner peripheral surface of the shaft cylinder portion 100. Proceed while bending. When the large-diameter opening end peripheral portion of the shaft cylinder portion 100 hits the plane of the mechanical chassis 62, the head portion 92 is disengaged from the shaft hole inner peripheral surface of the shaft cylinder portion 80, and the radial direction is generated by its own elastic return force. The shaft is resiliently restored, and is mounted in a predetermined state with its positioning portion 94 facing the end peripheral portion 102 of the shaft cylinder portion 100.

As described above, the driven side gear member 80 axially mounted on the shaft member 78 has the shaft cylinder portion 100 connected to the main shaft portion 84.
And the shaft portion including the sub shaft portion 86 is rotatably supported. At the same time, the shaft cylinder portion 100 is connected to the end peripheral portion 10 at one end.
2 is pressed by the positioning portion 94 of the sub shaft portion 86, and the other end is pressed by the flat surface of the mechanical chassis 62. Therefore, during normal rotation of the driven side gear member 80, the shaft cylinder 10
Numeral 0 rotates around the axis of the shaft member 78 while being supported in the axial direction so as to be sandwiched between the positioning portion 94 and the mechanical chassis 62 from both ends in the axial direction.

As shown in FIG. 1, the shaft member 78 is attached to a portion corresponding to the radial direction where the sub shaft portion 86 is arranged from the axis of the shaft member 78 in the driven gear member 80 which is mounted on the shaft member 78. When a load equal to or more than a predetermined value directed toward the distal end (in the direction of arrow C in the figure) acts, the countershaft portion 86 shown in FIGS.
The shaft cylinder portion 100 is pushed up in the direction of arrow C from the state where the end peripheral portion 102 of the shaft cylinder portion 100 is supported by the positioning portion 94.

As shown in FIG. 4, as the end peripheral portion 102 moves while sliding on the inclined guide portion 96, the sub shaft portion 86 bends toward the main shaft portion 84, and as shown in FIG. The driven gear member 80 is inclined with respect to 78. Also, in the state shown in FIG. 1 and FIG.
Since the second gear 02 is locked, the driven gear member 80 does not fall off the shaft member 78.

When the force acting on the driven gear member 80 in the direction of arrow C disappears, the elastic return force of the sub shaft portion 86 causes
The driven gear member 80 returns to the normal shaft support state shown in FIG. 2, FIG. 3, FIG. 7, and FIG.

As shown in FIGS. 1, 7, and 8, the drive-side gear member 82 has its shaft cylinder 112
Is mounted so as to be freely rotatable around the axis and movable in the axial direction. Further, the shaft member 114
The shaft portion of the shaft cylinder portion 112 is formed in a narrow hole from the step portion 118 correspondingly to the shaft portion from the step portion 116 at the intermediate predetermined position to the tip end. 8 is supported so as not to move toward the mechanical chassis 62 from the position shown in FIG.

A small drive gear 1 meshable with the large-diameter gear 108 is provided on the shaft cylinder 112 on the mechanical chassis 62 side.
20 are attached so as to rotate together. Further, the flange portion 12 formed integrally with the shaft cylinder portion 112 is formed.
A large sliding drive gear 126 is rotatably mounted on the shaft cylinder portion 112 so that a rotational torque equal to or less than a predetermined value can be transmitted to the two side surfaces via a sliding interlocking member 124 made of felt. The large sliding drive gear 126 is configured to mesh with the small diameter gear 106 of the driven gear member 80.

The drive side gear member 82 includes the shaft member 1.
14 and the stopper portion 128 and the shaft cylinder portion 11
A compression coil spring 130 is disposed between the two and biases them toward the mechanical chassis 62 until the state shown in FIG. 8 is reached. Furthermore, the shaft cylinder 112 and the large sliding drive gear 126
, A compression coil spring 132 is disposed between the sliding large driving gear 126 and the flange portion 122.
The rotation torque of up to a predetermined value can be transmitted by generating a constant frictional force between these components so as to sandwich them.

As can be understood from FIGS. 1, 6, 7 and 8, the switching operation for switching the gear switching device between the high speed state during fast forward or rewind and the normal speed state during play is performed by a play button. It is configured to be performed by pushing or returning operation of 56.

For this purpose, as shown in FIG. 6, an operation portion 136 is provided which is forked from a predetermined portion of the lever portion 134 provided integrally with the play button 56. Operation unit 1
As shown in FIG. 7 and FIG. 8, a guide slope 138 that rises obliquely from the side face on the mechanical chassis 62 side is formed at the tip end of the guide 36. In addition, the operation unit 136 is in a standby position where the operation unit 136 is disengaged from the driving-side gear member 82 in a state illustrated in FIGS. 6 and 8 in which the play button 56 is not pressed.

Therefore, when the play button 56 is in the standby state, the driving-side gear member 82 is caused to move by the urging force of the spring 130 so that the large driving gear 126 and the small-diameter gear 1 shown in FIG.
06 is set in a meshing state. In this state, the rotational driving force transmitted to the large sliding drive gear 126 is directly transmitted to the small-diameter gear 106, and the rotational speed is increased and transmitted due to the gear ratio therebetween.

Next, when the play button 56 is pressed, the operation section 136 inserts the tip of the guide slope 138 between the mechanical chassis 62 and the shaft cylinder 112 of the drive side gear member 82, and The entire drive gear member 82 is moved in the direction of arrow C along the slope 138.

By this operation, the sliding large driving gear 1
26 is disengaged from the small-diameter gear 106, and their meshing is released. At the same time, when the positions of the teeth of the small drive gear 120 and the large-diameter gear 108 of the driven gear member 80 can be meshed, they are meshed and set to the proper meshing state shown in FIG.

In this state, the rotational driving force transmitted to the large sliding drive gear 126 transmits a rotational torque less than a predetermined torque to the small driving gear 120 integrated with the flange portion 122 via the sliding interlocking member 124, The rotating force adjusted to a certain torque or less is transmitted to the large-diameter gear 108 meshing with the driving gear 120, and the rotational speed is reduced and transmitted due to the gear ratio between them. That is, when a braking force equal to or more than a predetermined value is applied to the driven gear member 80, the driven gear member 80 turns slowly or stops in the slipping interlocking member 124 portion of the drive gear member 82, or enters the stopped state. obtain.

If the position of each tooth of the small drive gear 120 and the large diameter gear 108 of the driven gear member 80 cannot be meshed when the play button 56 is pressed, the operation section 1
Small drive gear 120 moved in the direction of arrow C by 36
The drive-side gear member 82 is moved to the above-described play state in a state where the teeth of the large-diameter gear 108 are on the teeth.
At this time, the driven gear member 80 is moved in the direction of arrow C by the small drive gear 120 through the tooth portion of the large-diameter gear 108, so that the shaft cylinder portion 1 on the inclined guide portion 96 of the sub shaft portion 86.
The second gear member 80 is slid so as to push the end peripheral portion 102 so as to bend the sub shaft portion 86, and the driven gear member 80 is inclined with respect to the shaft member 78 as illustrated in FIG. 1.

In the state shown in FIG. 1, a relatively small elastic reaction force such as when the sub shaft portion 86 is bent is applied to the small drive gear 12.
It is in a state of acting only between the 0 tooth and the tooth of the large-diameter gear 108. Therefore, in the drive side gear member 82, even if the rotational driving force transmitted to the large sliding drive gear 126 is limited by the sliding interlocking member 124 to a relatively weak rotational force of a fixed value or less and transmitted to the small drive gear 120, This relatively weak rotational force overcomes the elastic reaction force of the countershaft portion 86 and the like acting between the small drive gear 120 and the large diameter gear 108 to move the small drive gear 120 and the large diameter gear 108 in relatively different directions. By moving the teeth, the teeth are brought into a meshing state, and the driven gear member 80 is returned to the state shown in FIG. In addition,
In the state shown in FIG. 1, the large-diameter gear 108 is
0, the displacement when moved in the direction of arrow C due to the large-diameter gear 10
8, the frictional resistance between the small drive gear 120 and the large-diameter gear 108 in a poor meshing state can be sufficiently reduced. Therefore, it is possible to reliably and easily transition from the poor meshing state shown in FIG. 1 to the proper meshing state shown in FIG.

Next, when releasing the play state, the other buttons 54, 58 or 60 are pressed and operated, and the operation section 136 is operated.
From the mechanical chassis 62 and the drive-side gear member 82. Then, the drive-side gear member 82 is returned from the state of FIG. 7 to the state of FIG. 8 by the urging force of the spring 130. During this operation, even if the large slip driving gear 126 rides on the small-diameter gear 106 and does not mesh, the relatively large rotational driving force directly transmitted to the large slip driving gear 126 causes the large-sliding driving gear to have a small diameter. Since the gear 106 is relatively rotated with respect to the gear 106, it is possible to cancel the poor meshing therebetween and shift to the proper meshing state shown in FIG.

Next, the configuration of the rotary drive system of the cassette recorder will be described with reference to FIG. In this cassette recorder, a drive motor 140 disposed on the mechanical chassis 62
The belt 146 is wound between the output pulley 142 of the first embodiment and the intermediate pulley 144 that is axially attached to the mechanical chassis to transmit the rotational force.

Further, each of the two reciprocating capstan flywheels 148 and 150 axially mounted at two predetermined positions of the mechanical chassis 62, and the intermediate intermediate pulley 1
As shown in FIG. 6, a single belt 152 is wound around 44 and the rotational force is transmitted.

Also, one flywheel 148 has
A drive gear 154 is provided integrally so as to be concentric with the rotation shaft. This drive gear 154 includes a mechanical chassis 6
The automatic gear 156 which is axially mounted on the second gear 2 is meshed. Further, the large gear drive gear 126 of the gear switching device is meshed with the automatic gear 156 to transmit the rotational force.

Next, the operation and operation of the rotating system of the cassette recorder according to the present embodiment configured as described above will be described.

In the case of running the tape at a high speed,
For example, at the time of fast-forward, the fast-forward button 54 is pressed and the switching lever member 74 of the traveling direction switching mechanism is turned on in FIG.
To the state shown by the imaginary line.

When the drive motor 140 is driven, the rotational driving force is generated by interlocking the intermediate pulley 144 as a belt winding mechanism with the belt 146 and further interlocking the flywheels 148 and 150 with the belt 152 to form a gear train. Drive gear 154, auto gear 156, large sliding drive gear 126, small diameter gear 106, output gear 110
And transmitted to the reel gear 70 via the connection gear 76,
A fast-forward operation is performed by rotating the second reel shaft 66 integral with the shaft at a high speed.

At the time of rewinding the tape to run at high speed, the rewind button 58 is pressed to switch the switching lever member 74 of the running direction switching mechanism to the state shown by the solid line in FIG.

When the drive motor 140 is driven, the rotational driving force is applied to the intermediate pulley 1 as a belt winding mechanism.
Further, the flywheels 148 and 150 are linked by the belt 152 while the link 44 is linked by the belt 146, and the drive gear 154, the auto gear 156, the large sliding drive gear 126, the small diameter gear 106, the output gear 110, and the connection gear forming a gear train The gear is transmitted from the idle gear 72 to the reel gear 68 via 76, and the first reel shaft 64 integrated therewith is rotated. By rotating the first reel shaft 64 in this way, the magnetic tape is wound around the hub rotated by the first reel shaft 64 of the tape cassette at a high speed.

In the play state in which the tape runs at the normal speed, the running direction switching mechanism has already been selectively switched by the operation of designating the running direction by a knob mechanism (not shown).
To switch the gear switching device to a normal speed state in which the small drive gear 120 and the large diameter gear 108 mesh.

When the drive motor 140 is driven, the rotational driving force is applied to the intermediate pulley 1 as a belt winding mechanism.
Further, the flywheels 148 and 150 are linked by the belt 152 while the link 44 is linked by the belt 146, and the drive gear 154, the auto gear 156 and the large-size drive gear 126, which constitute the gear train, are fixed to a certain value or less via the slip link member 124. Is transmitted to the small drive gear 120, from which the large diameter gear 108 and the output gear 1
10, transmitted to the connection gear 76. Here, when the traveling direction switching mechanism is switched to the forward traveling direction, the connection gear 76 is transmitted to the reel gear 70, and the second reel shaft 66 integrated therewith is rotated at a normal speed to thereby rotate the cassette tape. The magnetic tape is wound around the hub on the second reel shaft 66 side.

When the traveling direction switching mechanism is switched to the reverse traveling direction, the connecting gear 76
2, the rotational force is transmitted to the reel gear 68, and the first reel shaft 64 integral therewith is rotated at a normal speed, whereby the magnetic tape of the cassette tape is transferred to the first reel shaft 64.
Wrap around the hub on the side.

As described above, in the cassette recorder according to the present embodiment, the gear switching device is disposed at the most complicated portion of the structure related to the switching of the traveling direction in the rotating system. That is, the driven gear member 80 which is a part of the gear switching device
Are coaxially mounted on the switching lever member 74,
The large-diameter gear 108 and the small drive gear 12 of the driven gear member 80
0 when the engagement with the driven gear member 80 is not successful.
Is temporarily moved in the axial direction to escape, and the structure that causes the small drive gear 120 to engage when the small drive gear 120 is rotated is complicated, and is disposed in a portion where it is difficult to take means requiring a large number of parts. .

However, the gear switching device according to the present embodiment simply forms the positioning portion 94, the inclined guide portion 96, and the like, the end peripheral portion 102, and the like on the commonly used counter shaft portion 86 and the shaft cylinder portion 100. The simple structure that does not require separate parts allows the gears to mesh with each other, so that it is preferable because the configuration does not need to be complicated, and it is suitable for mass production and it is possible to provide an inexpensive product. .

[0076]

According to the gear switching device of the present invention, when the gears that can mesh with each other are shifted from the disengaged state to the meshed state, when one of the gears is not meshed, one of the gears can be engaged. A shaft member having a main shaft portion and a sub shaft portion divided into two for supporting a shaft cylinder portion of a gear, and a positioning portion provided on a head for preventing the sub shaft portion from coming off from an end peripheral portion of the shaft cylinder portion. Is disengaged, and the end guide operates the inclined guide portion that is continuous with the positioning portion, thereby bending the sub shaft portion and tilting the shaft cylinder portion of one gear with respect to the rotation axis of the shaft member. Elastic displacement.

This reduces the frictional resistance of the part where the gears are in contact due to poor meshing between the gears. When the gears in the non-meshing state are rotated with relatively small torque in relatively different directions. In addition, there is an effect that each tooth meshes with each other, and one of the gears is elastically returned to a state of being concentric with the shaft member, thereby achieving an appropriate meshing state. In addition, if a deflected warp structure portion is formed on the head of the countershaft portion, it can be prevented from coming off the shaft member when the shaft cylinder portion is inclined with respect to the rotation shaft.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a gear switching device provided in a rotary system of a cassette recorder according to an embodiment of the present invention, showing a meshing failure state of a gear switching device.

FIG. 2 is a main part perspective view of a main part and a sub-shaft part supporting and supporting a driven gear member in the gear switching device of the cassette recorder according to the embodiment of the gear switching device of the present invention. is there.

FIG. 3 is an enlarged sectional view of an essential part showing a normal bearing state of a sub shaft portion and a shaft cylinder portion of a driven gear member in a gear switching device of a cassette recorder according to an embodiment of a gear switching device of the present invention. .

FIG. 4 is an enlarged cross-sectional view of a main part showing a state in which a sub shaft portion is bent and a driven gear member is inclined obliquely in the gear switching device of the cassette recorder according to the embodiment of the gear switching device of the present invention.

FIG. 5 is an enlarged cross-sectional view of a main part illustrating another configuration of the inclined guide portion of the head of the countershaft in the gear switching device of the cassette recorder according to the embodiment of the gear switching device of the present invention.

FIG. 6 is a schematic plan view of a main part showing a rotation system of the cassette recorder according to the embodiment of the gear switching device of the present invention.

FIG. 7 is a vertical sectional view of a main part showing a state of the gear switching device of the cassette recorder according to the embodiment of the gear switching device of the present invention at the time of normal rotation.

FIG. 8 is a longitudinal sectional view of a main part of the gear switching device of the cassette recorder according to the embodiment of the present invention when the gear switching device is rotated at a high speed.

FIG. 9 is a longitudinal sectional view illustrating a main part of a gear change device of a cassette recorder that has been proposed in the related art;

[Explanation of symbols]

 56 play button 62 mechanical chassis 72 idle gear 74 switching lever member 76 connecting gear 78 shaft member 80 driven gear member 82 drive gear member 84 main shaft part 86 sub shaft part 92 head 94 positioning part 96 inclined guide part 98 reversing structure part REFERENCE SIGNS LIST 100 shaft cylinder portion 102 end peripheral portion 104 stepped portion 106 small diameter gear 108 large diameter gear 110 output gear 112 shaft cylinder portion 114 shaft member 120 small drive gear 122 flange portion 124 sliding interlocking member 126 sliding large drive gear

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazuo Takashima 1-2-1-11 Ikenohata, Taito-ku, Tokyo F-term in Iwa Corporation (reference) 3J028 EA02 EB02 EB12 EB35 EB42 EB63 EB67 FA11 FA21 FB05 FC32 FC43 FC49 FC68 GA32

Claims (2)

[Claims] A first gear and a second gear that can mesh with or separate from each other by relatively moving; and a main shaft portion and a sub shaft portion inside a shaft hole of a shaft cylinder portion of the first gear. A gear member configured to be inserted and a shaft member having a head provided so as to protrude at a tip of the countershaft portion facing one end peripheral portion of a shaft hole in the shaft cylinder portion; A positioning portion is formed on the head so as to be in contact with an end peripheral portion of the shaft cylinder portion and to maintain a predetermined pivotal support position when the first gear is in a normal rotation state, An inclined guide portion is formed in a slope shape, and when the first gear is urged in the moving direction by the movement of the second gear, the end peripheral portion of the first gear presses the inclined guide portion. The first gear is brought into contact with the shaft member by elastically bending the sub shaft portion by sliding contact with the shaft member. Gear-shift device being characterized in that configured to be inclined Te. 2. The head of the first gear, wherein when the shaft cylinder portion of the first gear is moved to an inclined state, the shaft member of the first gear is caught on the end peripheral portion to prevent the first gear from falling off. The gear switching device according to claim 1, wherein a reversing structure portion protruding from a free end side portion toward a base end direction of the countershaft portion and serving as a stopper is protruded.