JPH0410135B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is applicable to cassette tape recorders, VTRs,
This article relates to a cassette loading/unloading device installed in a DAT, etc.

[Conventional technology]

For example, in the case of a cassette tape recorder, the cassette loading/unloading device includes a cam driven by a drive source and a link mechanism operated by the cam. The cam is generally formed with a cam groove that engages one end of the link mechanism and guides the one end of the link mechanism to operate the link mechanism. Conventionally, there has been a device that drives a link mechanism for horizontal suction and ejection of a cassette, a link mechanism for vertically lowering and raising, etc. by rotating an integrally rotating cam member in the same direction (for example, in Japanese Patent Application Laid-Open No. 56-143559).

[Problem to be solved by the invention]

However, in a cassette tape recorder with an auto-reverse function, the link mechanism for bringing one of the pair of pinch rollers into contact depending on the tape running direction is driven by a moving means separate from the cassette moving mechanism. It had been. Therefore, it is necessary to rotate the drive cam for moving the cassette and the drive cam for controlling the pinch roller separately, and a plurality of drive motors are required, resulting in a complicated mechanism.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to improve the drive mechanism of a cassette-type magnetic recording/reproducing apparatus having an auto-reverse function.

[Means to solve the problem]

In order to solve the above problems, the cassette-type magnetic recording and reproducing apparatus of the present invention provides a cassette-type magnetic recording and reproducing apparatus that
Alternatively, it includes a driving force transmitting means for switching modes of magnetic recording and reproduction, and a rotating cam for guiding the operation of this driving force transmitting means. The driving force transmission means includes a horizontal motion transmission means for horizontally moving the cassette when it is sucked in and discharged, a vertical lowering and raising means for installing the sucked cassette in a running state, and an auto-reverse mechanism. The apparatus includes pinch roller switching means for selectively swinging the pair of pinch rollers according to the tape running direction. The rotary cam also includes a first cam member that drives the horizontal movement transmission means, a second cam member that drives the vertical descent and rise means, and a third cam member that drives the pinch roller switching means. . The first, second and third cam members are all driven by the rotation of the same drive motor in the same direction, and during the driving operation of any one cam member, the other two cam members The member is cammed so that it does not have a driving motion. Furthermore, the third cam member is configured to provide a
Driven with different reduction ratios.

[Effect]

When a cassette is inserted, the first, second and third cam members rotate together, the first cam member operates the horizontal suction and ejection means, and the cassette is sucked horizontally. While the horizontal suction and discharge means is operated by the first cam member, the second and third cam members are arranged to draw an arc of equal radius with respect to the rotation center of the cam, for example. Therefore, during this period, the vertical lowering and raising means that engages with the second cam member and the pinch roller swinging means that engages with the third cam member do not operate. After the horizontal suction of the cassette is completed, the radius of the second cam member changes at a predetermined rate from the center of rotation of the cam, for example. Therefore, the operation of the horizontal suction/ejection means is stopped, and the vertical lowering/elevating means is operated instead, so that the cassette is vertically lowered and installed in a running state. When the cassette is running, only the third cam member is driven, so that the pinch roller for auto-reverse is brought into contact in accordance with the running direction while the cassette is running.

[Embodiments of the invention]

An embodiment of the present invention will be described below using an auto-reverse type cassette tape recorder as an example. However, it should be pointed out in advance that the present invention is not limited to the cassette loading/unloading device of a cassette tape recorder, but can also be applied to VTRs and DATs.

FIG. 1 is a side sectional view showing the structure of a speed reduction unit for driving a cassette loading/unloading mechanism. The reduction unit is constituted by a planetary gear train 35.

Referring to FIG. 1, a power motor 31 is fixed to a main base 32 of a cassette tape recorder. The power motor 31 is a thin flat motor with a rotating shaft 3 protruding upward from the main base 32.
A pinion gear 34 is fixed to 3. The pinion gear 34 meshes with a planetary gear device 35 and drives the planetary gear device 35.

The planetary gear device 35 includes an internal gear 36, a fixed internal gear 37, an A planetary gear 38, an A carrier 41, a B planetary gear 42, a B carrier 43, and a C planetary gear 4.
It consists of 4. The internal gear 36, A carrier 41, and B carrier 43 are connected to the main base 32.
The cam posts 45 fixed to the cam posts 45 are inserted into the cam posts 45 in a stacked manner so that they can each rotate around the cam posts 45. Fixed internal gear 37
is fixed to the main base 32. The internal gear 36 includes a pinion gear 34 and an A planetary gear 38.
The cam post 45 rotates around the cam post 45 when the pinion gear 34 is driven. The rotational force of the internal gear 36 is transmitted to the A planetary gear 38. The A planetary gear 38 is rotatably supported by the A carrier 41, and rotates while meshing with the internal gear 36 and the fixed internal gear 37. Therefore, the rotational force of the internal gear 36 is reduced in speed via the A planetary gear 38 and transmitted to the A carrier 41. The gear formed on the A carrier 41 meshes with the B planetary gear 42. B
The planetary gear 42 is rotatably supported by the B carrier and rotates while meshing with the A carrier 41 and the fixed internal gear 37. Therefore, the rotational force of the A carrier 41 is reduced in speed via the B planetary gear 42 and transmitted to the B carrier 43. Furthermore, the gear formed on the B carrier 43 includes a C planetary gear 44.
are meshing together. By means of this C planetary gear 44, the mode switching cam 46 is set to a certain predetermined speed, and the cassette horizontal/head base retraction cam 4 is
7 and cassette vertical cam 48 are also driven at another predetermined speed.

The operation mode switching cam 46 is rotatably engaged with the B carrier 43 and rotates around the B carrier 43, or in other words, the cam post 45. A cam groove 51 having a predetermined loop shape (endless shape), which will be described later, is formed on the lower surface side of the operation mode switching cam 46. An operating swing link 52 is fitted into the cam groove 51 . Therefore, the rotation of the operation mode switching cam 46 drives the operation swing link 52. Note that a roller 53 is inserted between the cam groove 51 and the operating swing link 52,
Efforts are made to reduce the frictional force that occurs between the two, allowing for smooth transmission of movement.

A locking recess 54 is formed in a part of the outer peripheral surface of the operation mode switching cam 46. A lock pin 55 can be engaged with the locking recess 54 .

A horizontal cassette with a support shaft for the C planetary gear 44.
The head base retraction cam 47 is rotated about the cam post 45 by the rotation of the C planetary gear 44. A notch 61 is formed in a part of the outer peripheral surface of the lower surface of the cassette horizontal/head base retraction cam 47, and a head base retraction link 62 is formed in this notch 61.
is engaged. Therefore, by rotating the cassette horizontal/head base retraction cam 47,
The head base retraction link 62 is selectively brought into contact with the notch 61 or the outer peripheral surface of the cassette horizontal/head base retraction cam 47.
2 is rocked.

A cam groove 63 is formed on the upper surface side of the cassette horizontal/head base retraction cam 47. Cam groove 6
3 is a predetermined loop-shaped endless groove, as will be described later. One end of a cassette horizontal swing link 64 is engaged with this cam groove 63. Therefore, the cassette horizontal/head base retraction cam 47
As a result of this rotation, the cassette horizontal swing link 64 performs a predetermined swing motion. Note that a roller 65 is also inserted between the cam groove 63 and the cassette horizontal swing link 64 in order to prevent friction between the two and smooth the engagement between the two.

A cassette vertical cam 48 is fixed to the cassette horizontal/head base retraction cam 47. Therefore, the cassette horizontal/head base retraction cam 47
As the cassette vertical cam 48 rotates, the cassette vertical cam 48 similarly rotates about the cam post 45. A cam groove 66 is formed on the lower surface of the cassette vertical cam 48. One end of a cassette vertical swing link 68 is engaged with this cam groove 66 via a roller 67.

In this embodiment, the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48 are made separately and are fixed together, but the cassette horizontal/head base retraction cam 48 and the cassette vertical cam 48 are integrated. It may be molded into

A notch 71 is formed in a part of the outer peripheral surface of the cassette horizontal/head base retraction cam 47. A lock pin 55 can be engaged with this notch 71.

Lock pin 55 is a protrusion formed on lock plate 56. The lock plate 56 can move vertically as shown by an arrow 59, and when it moves downward as shown, the lock pin 55 moves into the locking recess 54 of the operation mode switching cam 46.
, and prevents rotation of the operation mode switching cam 46. Further, when the lock plate 56 moves upward, the lock pin 55 engages with the notch 71 of the cassette horizontal/head base retraction cam 47 to prevent the rotation of the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48. has been done. As described above, the movement of the lock plate 56 causes the lock pin 55 to move to the operating mode switching cam 46 or the cassette horizontal/head base retraction cam 47.
(and the cassette vertical cam 48), the operation mode is fixed at a predetermined mode when the cassette tape is moved, and the cassette is not loaded or ejected while the cassette tape is being driven.

Note that the mode switching brush 72 provided on the upper surface of the cassette vertical cam 48 is configured to come into contact with a mode switch circuit 74 provided on the lower surface of the upper base 73, and the mode switching brush 72 and the mode switching brush 72 are arranged on the lower surface of the upper base 73. Depending on the switching circuit 74 and the contact position, the cassette vertical cam 48
(and cassette horizontal/head base retraction cam 4)
7), that is, the current position for driving the cassette is detected.

Next, FIGS. 2 and 3 will be explained. Second
3 through 3 are diagrams for explaining a link mechanism driven by the cassette horizontal/head base retraction cam 47 of FIG. 1.

First, FIG. 2 is a plan view showing a horizontal blow-in and discharge mechanism for cassette tapes. And Figure 3 is
FIG. 3 is an exploded perspective view for explaining the coupling relationship between the cassette horizontal/head base retraction cam 47 shown in FIG. 2 and the link mechanism. First, the horizontal blow-in and discharge mechanism for cassette tapes will be explained with reference to FIGS. 2 and 3.

As explained in FIG. 1, a cam groove 63 for horizontally swinging the cassette is formed on the upper surface of the cassette horizontal/head base retraction cam 47. The cassette horizontal swing link 64 has a substantially V-shaped or substantially fan-shaped planar shape, and its leading end is rotatably supported by a post 81 protruding from the main base 32. One end of the cassette horizontal swing link 64 engages with the cam groove 63 as described above, and a gear 82 is formed at the other end. A horizontal connection link 84 is connected via an arc amplification gear 83 that meshes with this gear 82. The arc amplifying gear 83 and the horizontal connecting link 84 are connected to the holder spring 8
6 and 87 and a biasing spring 88, it is rotatably passed through a post 85 that projects vertically upward from the main base 32. The holder spring 86 connects the arc amplification gear 83 and the horizontal connection link 84 to the second
In the figure, it is engaged with the circular amplification gear 83 and the horizontal connection link 84 so as to rotate it counterclockwise. Further, the holder spring 87 is engaged with the arc amplification gear 83 and the horizontal connection link 84 so as to rotate the arc amplification gear 83 and the horizontal connection link 84 clockwise in FIG. Then, the holder spring 86 and the holder spring 8
7 are both biased by a biasing spring 88, and the arc amplifying gear 83 and the horizontal connecting link 8
4 in each of the above-mentioned rotational directions. Therefore, the arc amplifying gear 83 and the horizontal connecting link 84
are always kept in a balanced state by holder springs 86 and 87.

The arc amplification gear 83 is connected to the cassette horizontal swing link 6
This is for amplifying the movement of 4 and transmitting it to the horizontal connecting link 84. The horizontal connecting link 84 is a bent longitudinal member, and one end is connected to the post 8 as described above.
5 is rotatably supported, and the other end has a longitudinal small hole 91.
is formed. Slide piece 9 into the small hole 91
The two protrusions 93 are slidably engaged in pairs.
The slide piece 92 is slidable along the long groove 95 of the arm EV94, and is used to position the cassette tape 96 in the insertion direction. arm
The EV94 is supported by a base EV97 and a holder EV98 with its rear end (the frontmost part in the cassette insertion direction) as the center of rotation. and,
The tip end piece of the arm EV (the rearmost end piece in the cassette insertion direction) engages with the holder cassette 101 so as to lift it up. Furthermore, an engaging protrusion (not shown) at the upper left end in FIG. 2 engages with the vertical link 103, as shown in FIG. 4.

Next, FIGS. 4 to 6 are diagrams for explaining the vertical lowering and raising mechanism of the cassette tape.
Particularly, FIG. 4 is a plan view, FIG. 5 is a side view, and FIG. 6 is an enlarged perspective view of a connecting portion of the swing link.

Referring to FIGS. 4 to 6, the lower surface of the cassette vertical cam 48 has a cam groove 6 as described above.
6 is formed, and one end of a cassette vertical swing link 68 is engaged with this cam groove 66. The cassette vertical swing link 68 is connected to the vertical connecting link 1
03 and a biasing spring vertical 104, it is rotatably supported by a post 102 that projects vertically upward from the bottom base. The cassette vertical swing link 68 and the vertical connection link 103 are connected by a biasing spring vertical 104, and the positional relationship between the cassette vertical swing link 68 and the vertical connection link 103 is in a predetermined positional relationship. elastically connected. The tip of the vertical connection link 103 engages with an engagement protrusion 105 of the arm EV94.

Next, the operation of the cassette tape loading/unloading mechanism will be explained with reference to FIGS. 2 through 6.

Before the cassette tape 96 is inserted, the cassette tape loading/unloading mechanism is in the state shown in FIG. In this state, when the cassette tape 96 is inserted in the direction of the arrow 106, the distal end engaging portion 108 of the slide piece 92 engages with the reel hole 107 on the insertion direction side of the cassette tape 96. next,
A cassette horizontal/head base retraction cam 47 is rotated by the planetary gear set 35 described in FIG. Then, a predetermined loop-shaped cam groove 63 is formed on the surface of the cassette horizontal/head base retraction cam 47 eccentrically with respect to the rotation center axis of the cam 47.
, the cassette horizontal swing link 64 moves, and the movement is amplified by the arc amplification gear 83 and transmitted to the horizontal connection link 84. The horizontal connecting link 84 then rotates in the direction of the arrow 111 in FIG. 2, causing the slide piece 92 to slide. With this, the cassette tape 96 is attached to the holder cassette 10.
1. After the cassette tape 96 is loaded into the holder cassette 101, the cassette vertical swing link 68 is rotated in response to the rotation of the cassette vertical cam 48 shown in FIG. 4, and the rotation is transmitted to the vertical connection link 103. Therefore, the vertical connection link 103 causes the arm EV94 to rotate around the base EV (and the holder EV98, not shown), as shown by the dashed line in FIG. Therefore, the holder cassette 101 is lowered from the state in which the arm EV94 and its upper surface are lined up horizontally, and becomes the state shown by the dashed line in FIG. This state is the state in which the cassette tape 96 is mounted in the so-called PLAY state.

In the ejecting operation of the cassette tape 96, the cassette tape mounting/ejecting mechanism operates in the reverse order by the rotation of the cassette vertical cam 48 and the cassette horizontal/head base retraction cam 47, and the cassette tape 96 is ejected. In this case, the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48 rotate 180 degrees in a predetermined direction to place the cassette tape 96 in the attached state, and further rotate 180 degrees in the same direction to place the cassette tape 96 in the ejected state. do.
In other words, the cassette horizontal/head base retraction cam 4
7. One rotation of the cassette vertical cam 48 completes one cassette tape blowing and discharging operation.

7 and 8 are views for explaining the head base retraction mechanism, in particular, FIG. 7 is a plan view, and FIG. 8 is a partial side view of the mechanism.

With reference to FIGS. 7 and 8, reference numeral 47
is a cassette horizontal/head base retraction cam.
The planar shape of the cassette horizontal/head base retracting cam 47 shown in FIG. 7 is different from the planar shape of the cassette horizontal/head base retracting cam 47 shown in FIG. Figure 7 shows the cassette horizontally and vertically to explain the operation of the head base retraction mechanism.
This is because only the outer peripheral shape of the lower half of the head base retraction cam 47 is drawn. In other words,
Cassette horizontal/head base retraction cam 4 in Fig. 7
The shape 7 indicates the outer peripheral shape of the portion of the cam 47 shown in FIG. 1 that is in contact with the head base retraction link 62.

The head base retraction link 62 is a longitudinal member, one end of which is rotatably supported by a post 81. And the other end is A link 11
It is in contact with 2. Head base retraction link 62
The center portion of the head base retraction link 62 is in contact with the peripheral surface of the cassette horizontal/head base retraction cam 47, and as the cam 47 rotates, the head base retraction link 62 is swung around the post 81. A-link 112 is a laterally disposed elongated member. The head base retraction link 62 side is connected to the main base 32.
It is slidably supported by a pin 113 protruding from the side wall of. Further, the other end engages with the upper end of the B link 114 in a point-to-point manner. The B link 114 is attached to the side wall of the main base 32 by a pin 115 and rotates around the pin 115. The lower end of B link 114 is C link 1
It is engaged with one end of 16 in a rotating pair. The C-link 116 is a longitudinal member arranged parallel to the main base 32, and the C-link 116 is a longitudinal member arranged parallel to the main base 32.
It is rotatably provided around 18. A protrusion 119 is provided at the other end of the C-link 116, and the protrusion 119 engages with a head base 121. The head base 121 is a substantially T-shaped base,
It is slidably held relative to the main base 32 by three guides 122, 123, and 124. A magnetic head 125 is placed in the center of the head base 121. Furthermore, a spring 126 is hung on the head base 121.
26, the head base 121 is urged leftward in FIG.

Next, the operation of the head base retraction mechanism will be explained. The head base retraction mechanism moves the head 125 backward, that is, to the right in FIG.
This is a mechanism that moves the cassette tape so that it does not get in the way of loading and unloading the tape. Then, when playing the cassette tape, the head 125 is moved to the seventh position so that the head 125 comes into contact with the tape surface of the cassette tape.
It is to be placed in the state shown in the figure.

Now, considering the PLAY state, in that state the cassette horizontal/head base retraction cam 47 is in the state shown in FIG. That is, the notch of the cassette horizontal/head base retraction cam 47 is in contact with the head base retraction link 62. Therefore, the A link 112 is relatively A of the arrow 127.
It is in a state of movement in the direction. Therefore, in this state, the lower end of the B link 114 is on the B side of the arrow 128, and one end of the C link 116 is swung toward the B side of the arrow 129. Therefore, C link 11
The head base 121 that engages with the other end of the seventh
It is located on the left side in the figure, and the head 125 is in contact with a tape surface (not shown).

On the other hand, when loading and ejecting a cassette tape, the cassette horizontal/head base retracting cam 47 rotates, and the head base retracting link 62 comes into contact with the circumferential surface of the cassette horizontal/head base retracting cam 47. Therefore, the head base retraction link 62 is rotated to the right about the post 81 from the state shown in FIG. 7 by the circumferential surface of the cassette horizontal/head base retraction cam 47. When this state is reached, the A link 112 is slid in the direction of arrow 127 by the other end of the head base retraction link 62. Therefore, the lower end of the B link 114 moves in the direction A of arrow 128, and one end of the C link 116 swings in the direction A of arrow 129. Therefore, the head base 121 that engages with the other end of the C-link 116 is moved to the right in FIG. 7 against the force of the spring 126. Therefore, the head 125 is retracted to the right from the state of contact with the tape surface.

FIG. 9 shows the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 4 described above.
This is a summary of the rotation angles of No. 8 and the positional relationships between the link mechanisms driven by the rotation angles. In Figure 9, the cassette horizontal and
For convenience of explanation, the head base retraction cam 47 is shown separately as a cassette horizontal cam and a head base retraction cam. And, as explained earlier,
These cassette horizontal cam, cassette vertical cam, and head base retraction cam rotate integrally about the same axis 45. One rotation (360 degrees) completes one cycle of loading and unloading the cassette tape. To this end, the cassette horizontal cam and the cassette vertical cam are formed with predetermined loop-shaped cam grooves 63 and 66 eccentric to the cam rotation axis, the radius of which varies around the cam rotation axis.

FIG. 10 is a diagram showing the shape of the cam groove 63 formed in the cassette horizontal/head base retraction cam 47 and the positional relationship between it and the notch 61. The horizontal cam groove 63 has a shape that is symmetrical to the line connecting the EJECT and PLAY positions. In the EJECT state, the center radius of the cam groove 63 is the largest r _EH
It is designed to be. The radius of the cam groove 63 gradually decreases during 75 degrees from the EJECT state until the cassette horizontal/head base retraction cam 47 rotates clockwise and reaches point A.
The radius of is r _PH . And from that state
During the 120° to point B including the PLAY point, the cam groove 6
3 is constant with the radius r _PH . And from point B
The radius of the cam groove 63 is designed to gradually increase within 75 degrees up to EJECT. In this way, the horizontal cam groove 63 of the cassette horizontal/head base retraction cam 47 is farthest from the cam center in the EJECT state, and conversely, the cam groove is closest to the cam center in the PLAY state and before and after that. It is a loop-shaped groove that is eccentric with respect to the center of the cam. Therefore, as the cassette horizontal/head base retraction cam 47 rotates, the state of the eccentric loop-shaped groove changes, and the engaging portion of the link is guided. In addition, notch 7
1 is for the lock pin 55 to engage with.

FIG. 11 is a diagram showing the shape of the vertical cam groove 66 formed in the cassette vertical cam 48. The vertical cam groove 66 also has a shape that is symmetrical to the line connecting EJECT and PLAY. The center of the cam groove 66 is set to have a radius _rEV with respect to the cam center within a range of 150 degrees around EJECT. Then, the cassette vertical cam 48 rotates clockwise from EJECT, and the radius of the cam groove 66 gradually increases from r _EV to r _PV during 60 degrees from point C to point D. The radius of the cam groove 66 is r _PV during the 90° period centered on PLAY from point D to point F, and the radius of the cam groove 66 during the 60° period from point F to point G is rPV. gradually decreases from r _PV to r _EV . Therefore, depending on the rotation of the cassette vertical cam 48, the cassette vertical cam 4
The radius of the cam groove 66 relative to the center of the link 8 changes, the engaging portion of the link is guided, and the link moves in a predetermined manner.

FIG. 12 is a plan view for explaining the pinch roller switching mechanism. Since the cassette tape recorder of this embodiment has an auto-reverse mechanism, the two pinch rollers are alternately switched depending on the direction of rotation of the cassette tape. Referring to FIG. 12, operation mode switching cam 4
6 has a cam groove 51 formed therein. One end of the longitudinal swing link 52 is rotatably supported by the post 81. A protrusion 131 is provided at the longitudinal center of the operating swing link 52, and the protrusion 131 forms a sliding pair with the cam groove 51. The other end of the operating swing link 52 is a D link 132
is engaged with. The D link 132 slides in the direction of an arrow 133 in response to the movement of the swinging link 52. The other end of D link 132 is E link 1
34. E-link is main base 3
The D-link 132 rotates around a pin 135 provided in the cam CH136, and the movement of the D-link 132 is transmitted to the cam CH136. The cam CH136 is a plate-shaped elongated member as shown in the drawing arranged parallel to the main base 32, and is held by guides 137 and 138 fixed to the main base 32, and its sliding direction is guided. Then, the cam CH136 slides in the direction of the arrow 139. Pinch rollers 141 and 142 are provided in relation to both ends of cam CH136, respectively. In other words, the pinch rollers 141 and 142 are attached to the posts 143 and 144 on the main base 32, respectively.
The stopper 145, 146 is adapted to engage with the notch 147, 148 of the cam CH136 in a predetermined state, respectively. Due to the shape of the notches 147 and 148, in the state shown in FIG. 12, the cam CH136 is moving in the direction A of arrow 139, the pinch roller 141 is in operation, and conversely the cam CH136 is moving in the direction B of arrow 139. At this time, the pinch roller 142 is configured to be in an operating state. Such sliding motion of the cam CH136 is caused by the operation swing link 52, the D link 132, and the E link 1 which are swung by the rotation of the operation mode switching cam 46.
34.

FIG. 13 is a diagram for explaining the shape of the cam groove 51 formed in the operation mode switching cam 46. The cam groove 51 has a symmetrical shape laterally and vertically. Then, at point L in FIG. 13, the operating mode switching cam 46 is in a state farthest from the center.
At point R, you are closest to the center. When the protrusion 131 of the operating swing link 52 is located at the L point, the left pinch roller 141 is in the operating state, and when the protrusion 131 is located at the R point, the right pinch roller 142 is in the operating state. It is being done. In this way, in this embodiment, when the operation mode switching cam 46 rotates once, the pinch roller 1
41 and 142 can be switched twice. The four locking recesses 54 symmetrically formed in the operation mode switching cam 46 are connected to the lock pin 55.
It is something that engages with.

As shown in FIG. 1, the operation mode switching cam 46 is driven at a different reduction ratio than the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48. Therefore, since it is driven by a different output gear from the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48, the cassette horizontal/head base retraction cam 47 is driven by a different output gear.
conversely, when the operation mode switching cam 46 is operated, the operation of the cassette horizontal/head base retraction cam 47 can be stopped. The lock pin 55 protruding from the lock plate 56 is for this purpose. Therefore, depending on the operating state of the cassette tape recorder, the lock plate 56 (see FIG. 1) slides up and down to selectively lock the cassette horizontal/head base retraction cam 47 or the operating mode switching cam 46 inoperable. do.

〔Effect of the invention〕

According to this invention, a series of operations in which a cassette is sucked in horizontally, lowered vertically, mounted in a ready-to-run condition, raised vertically, and discharged horizontally, and the swinging of the pinch roller for auto-reverse operation are performed. Since driving is performed by unidirectional rotation of the integrally rotating cam member, a cassette-type magnetic recording/reproducing device with smooth movement and a compact drive mechanism can be achieved.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the structure of the speed reduction unit. FIG. 2 is a plan view showing the horizontal suction and discharge mechanism for the cassette tape. FIG. 3 is an exploded perspective view for explaining the coupling relationship between the cam and the link mechanism. FIG. 4 is a plan view illustrating a mechanism for vertically lowering and raising a cassette tape. Fifth
The figure is a side view for explaining a mechanism for vertically lowering and raising a cassette tape. FIG. 6 is an enlarged perspective view of the coupling portion of the swing link. FIG. 7 is a plan view of the head base retraction mechanism. FIG. 8 is a partial side view of the head base retraction mechanism. FIG. 9 is a diagram showing the rotation angles of the cassette horizontal/head base retraction cam 47 and the cassette vertical cam 48 and their positional relationship with the link mechanism. Figure 10 shows
6 is a diagram showing the shape of a cam groove 63 of the cassette horizontal/head base retraction cam 47. FIG. FIG. 11 is a diagram showing the shape of the cam groove 66 of the cassette vertical cam 48. FIG. 12 is a plan view showing the pinch roller switching mechanism. FIG. 13 is a diagram showing the shape of the cam groove 51 of the operation mode switching cam 46. In the figure, 47 is a cassette horizontal/head base retraction cam, 48 is a cassette vertical cam, 61 is a notch, 62 is a head base retraction link, 63 is a cam groove, 64 is a cassette horizontal swing link, 66 is a cam groove, and 68 is a cassette vertical Swing link, 84 is a horizontal connection link, 92 is a slide piece, 94 is an arm
EV, 96 is a cassette tape, 101 is a holder cassette, 103 is a vertical connection link, and 105 is an engaging protrusion.

Claims (1)

[Scope of Claims] 1. A cassette-type magnetic recording device including a driving force transmitting means for mounting and ejecting a cassette or switching modes of magnetic recording and reproduction, and a rotating cam for guiding the operation of this driving force transmitting means. In the playback device, the driving force transmission means includes a horizontal movement transmission means for horizontally moving the cassette during suction and ejection of the cassette, and a vertical descent and rise for mounting the sucked cassette in a traveling state. and pinch roller switching means for selectively swinging a pair of pinch rollers for auto-reverse according to the tape running direction, and the rotary cam drives the horizontal movement transmission means. a first cam member; a second cam member that drives the vertical descent/lift transmission means; and a third cam member that drives the pinch roller switching means; The cam members are all driven by the rotation of the same drive motor in the same direction, and while any one cam member is in drive operation, the other two cam members are not driven. A cassette-type magnetic recording and reproducing apparatus, wherein a cam curve is formed, and the third cam member is driven at a different reduction ratio through an output gear different from that of the first and second cam members.