JPH0542066B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to an end detection device for a duplex tape recorder in which a plurality of cassette tapes are loaded into one cassette tape storage section.

(B) Conventional technology As seen in, for example, Japanese Utility Model Application Publication No. 57-67267, a conventional duplex tape recorder stores a plurality of cassette tapes in one tape storage section and mutually connects them to a common capstan shaft. An end detection device for a duplex tape recorder has been proposed in which an arbitrary cassette tape is run using a plurality of pinch rollers that operate independently, and the end of the tape is detected using the tape tension at the end of the tape. .

(c) Problems to be Solved by the Invention However, in the conventional duplex tape recorder, the end of the duplex tape recorder is detected using the tape tension at the end of the tape. It becomes impossible to perform termination detection. Therefore, the end of the tape has been detected when the reel cap or reel stand on which the first or second cassette tape is mounted stops rotating. However, in this case, a separate end detection device must be provided on the reel cap or reel stand on which the first or second cassette tape is mounted, which complicates the mechanism.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an end detection device for a duplex tape recorder that can simplify the mechanism of the end detection device.

(d) Means for Solving the Problems This invention has been made to solve the above problems, and includes storing two cassette tapes, the first and second cassette tapes, in a stacked manner in one tape storage section, and One capstan shaft corresponds to the cassette tape, and the first,
In a dual tape recorder that selectively runs the first and second cassette tapes at a constant speed by abutting the first and second pinch rollers corresponding to the second cassette tape, respectively, an eccentric swing cam and a drive are used. A first sensor lever having a sliding protrusion that can come into sliding contact with the swinging cam and the drive cam is rotatably provided on a rotating body that includes a cam and is driven by an appropriate drive source, and the first sensor lever is rotatably swingable. Pushing means is provided on the reel cap side to which the tape is attached, and receives the rotational force of the reel cap and cooperates with the swing cam to rotate and swing the first sensor lever. When the reel cap is rotating, the swing cam and the pushing means rotate and swing the reel cap within a range that does not apply any acting force to the actuated means, and
A second sensor lever is rotatably provided with a sliding protrusion that can come into sliding contact with the rocking cam and drive cam of the rotating body, and a gear or the like is mounted on the reel stand side on which the second cassette tape is mounted. A pushing means is provided which receives the rotational force of the reel stand via a connecting member and rotates and swings the second sensor lever in cooperation with the swing cam, and the reel stand is connected to the second sensor lever. During the rotation of the first or second actuated means, the swing cam and the pushing means rotate and swing within a range that does not apply any acting force to the actuated means.
At the end of the tape in tape mode, when the rotation of the reel cap or reel stand on the selected side stops, the first or second sensor lever, which had been rotating and swinging, is activated by the reel cap or reel stand on the stopped side. After the sliding protrusion of the sensor lever is brought to the top dead center position of the rocking cam by the action of the swing cam, the sliding protrusion is driven by the driving cam, and each sensor lever is activated. The present invention provides a terminal end detection device for a duplex tape recorder, characterized in that it is configured to apply an acting force to the means.

(E) Effect According to the present invention, the first and second sensor levers are brought into sliding contact with the rocking cam of the same rotary body to rotate and rock, so that at the end of the tape in the first or second tape mode, Since the end is detected by the sensor lever on the selected side, the end detection device in the duplex tape recorder has a simple structure.

(f) Examples The present invention will be described in detail below based on examples shown in the figures. Note that this invention is not limited thereby.

FIG. 1 shows the arrangement when the cassette tape is installed in this embodiment. A plurality of cassette tapes, for example two cassette tapes 1 and 2, are connected to a capstan 3 for FOR travel.
A capstan 4 for REV running and a reel stand (not shown) are placed one on top of the other so that they are coaxial, and a magnetic head 5 and a pinch roller 6 are placed opposite the magnetic tape surface of the cassette tape 1.
In addition, a magnetic head 7 and two pinch rollers 8 and 9 are placed opposite the magnetic tape surface of the cassette tape 2.
and place it. The two magnetic heads 5, 7 are attached to the same reference stand 10, and each pinch roller 6, 8, 9 is structured to be able to move independently.

FIG. 2 shows an example of the arrangement of operation buttons. In this example, for two cassette tapes, one plays only FOR, PLAY, and fast forward.
FF, rewind REW, stop/eject STOP/
It has each function of EJECT, and the other is FOR,
FEV both playback PLAY and recording REC, fast forward FF,
It has the following functions: rewind REW, stop/eject STOP/EJECT, and pause PAUSE. In the following explanation, the FOR only playback device located above the two cassette tapes will be abbreviated as T ₁ , and the FOR and REV bidirectional recording and playback device located below will be abbreviated as T ₂ . .

The tape recorder in this embodiment operates in a continuous playback mode in which FOR and _FEV of T2 are played continuously after the end of playback of _T1 , a one-cycle mode and a continuous mode in _T2 , and a continuous playback mode in which playback is performed in _T1 and simultaneously in _T2. You can select from four editing modes for recording. Furthermore, in edit mode, PLAY
T ₁ and T ₂ operate by operating both the and REC buttons, and only T ₁ is played by operating only the PLAY button.

FIGS. 3a and 3b show a sensor section for detecting the end of a cassette tape. The shaft 12 fixed to the take-up reel cap 1 to which the cassette tape 1 on the T ₁ side is attached is connected to the main chassis 13.
A receiving plate 14 is rotatably inserted into a hollow shaft 13a formed in the main chassis 13, and is fixed to a portion protruding from the back side of the main chassis 13. In addition, the receiving plate 14
A termination detection sensor 15 having a pressing protrusion 15a is attached to the lower shaft 12. This end detection sensor 15 is pressed against a stop plate 17 attached to the shaft 12 by the biasing force of a spring 16 installed between the receiving plate 14 and the rotation of the take-up reel cap 11 is transmitted to the end detection sensor 15. It is becoming more and more like this. When the take-up reel cap 11 rotates, that is, T ₁
During operation, the pressing protrusion 15a of the end detection sensor 15 is pressed against the shaft 18a fixed to the back chassis 18.
Sensor lever 19 rotatably attached to
A sliding protrusion 19b protruding from the sensor lever 19 and directed toward the back chassis 18 presses the contact surface 19a of the back seat 18.
An eccentric rocking cam 20 formed coaxially with an end cam 20 as a rotating body rotatably held in
It slides on the circumferential surface of a. End cam 20 is indicated by arrow F
In addition to the swinging cam 20a, the end cam 20 also includes a sensor lever 19 located outside of the swinging cam 20a, which slides into sliding contact with the sliding protrusion 19b by an outer surface 20b when the sensor lever 19 is rotated in the direction of arrow E. A cam 20c is formed as an arc-shaped driving cam.

During the operation of _T1 , when the rotation of the take-up reel cap 11 stops at the end of the cassette tape,
Along with this, the rotation of the end detection sensor 15 also stops, and the pressing protrusion 15a of the end detection sensor 15 no longer presses the sensor lever 19. The sliding protrusion 19b of the sensor lever 19 is pressed to the maximum diameter part of the swinging cam 20a by the end cam 20 rotating in the direction of arrow F, and then the sliding protrusion 19b of the cam 20c is pressed against the outer surface 20b of the cam 20c.
, and rotate the sensor lever 19 in the direction of arrow E using the shaft 18a as a fulcrum. sensor lever 1
9 stops the operating state of _T1 , as will be described later, by pressing a pin of an end select lever (not shown) that comes into contact with the arm 19c.

On the other hand, a hollow shaft 1 formed in the main chassis 13
A take-up reel stand 21 on which the cassette tape 2 on the _T2 side is mounted is inserted through the outer periphery of the tape 3a. The take-up reel stand 21 is provided with a gear 22 held by the main chassis 13 at a position that meshes with a gear 21a provided on the lower end surface thereof.
The support shaft 23 of the gear 22 that protrudes from the gear 22 to the back side of the main chassis 13 has an autostop having a receiving plate 24 and a pressing protrusion 25a, as in the case of the shaft 12 fixed to the take-up reel cap 11. A sensor 25 is attached. The auto-stop sensor 25 is pressed against a stop plate 27 attached to the support shaft 23 by the biasing force of a spring 26 attached between the support plate 24 and the rotation of the take-up reel stand 21 is transmitted to the auto-stop sensor 25. It is becoming more and more common. When the take-up reel stand 21 rotates, that is, during the _T2 operation, the pressing protrusion 25a of the auto-stop sensor 25 is pressed against the shaft 18b fixed to the back chassis 18.
sensor lever 28 rotatably attached to
A sliding protrusion 28b, which presses against the contact surface 28a of the sensor lever 28 and extends toward the back chassis 18, is slid on the circumferential surface of the swing cam 20a, which is integrated with the end cam 20.

During the operation of _T2 , when the rotation of the take-up reel stand 21 stops at the end of the cassette tape, the rotation of the gear 22 also stops, and the pressing protrusion 25a of the auto-stop sensor 25 presses the sensor lever 28. It disappears. sensor lever 28
, rotates in the direction of arrow E about the shaft 18b as a fulcrum, as in the case of the _T1 side, and presses a pin of an end select lever (not shown) that is in contact with the arm portion 28c, thereby stopping the operating state of _T2 .

As explained above, in the tape recorder of this embodiment, the two sensor levers 19 and 28, which operate by being transmitted with the rotation of the reel cap 11 on the _T1 side and the reel stand 21 on the _T2 side, are connected to the same end cam 2.
0, rotates the sensor levers 19 and 28 at the end of the cassette tape, presses the end select lever, and selects T ₁ and T ₂ .
It is designed to stop or switch the operation of the In addition, in the tape recorder of this embodiment, the end detection mechanism that stops the rotation of the take-up reel cap 11 and the take-up reel stand ₂₁ starts operating; It is equipped with a blocking mechanism that operates in accordance with each mode to prevent malfunctioning termination detection operations when only the _T2 side is operated. This blocking mechanism will be described later.

4 to 9 are diagrams showing the structure of the tape recorder mechanism in this embodiment. In FIG. 4, which shows the state in the editing mode, the mode select lever 30 disposed on the side of the sensor lever 28 has a continuous U-shape, and has a long U-shaped portion. A pin 30b that engages with a hole 30a allows it to slide in the directions of arrows C and D in the figure. A positioning pin 30c is formed in the U-shaped portion of the mode select lever 30 and projects toward the mode setting plate 31 having a plurality of V-shaped recesses. When the positioning pin 30c engages with the recess 31a of the mode setting plate 31, it enters the editing mode, when it engages the recess 31b, it enters the continuous mode at _T2 , when it engages the recess 31c, it enters the one cycle mode at _T2 , and When engaged with the recessed portion 31d, the continuous mode is set.

Further, the mode select lever 30 has a pin 30d projecting downward from the upper end of the U-shaped portion. This pin 30d has a convex shape that presses an inclined surface 32a formed on one side of the end select lever 32 and rotates the end select lever 32 in the E direction around the shaft 32f when the positioning pin 30c selects the edit mode. The portion 32b is moved to the position where it engages with the pin 33a formed on the lock plate release lever 33. At the tape winding end time, as each sensor lever 19, 28 on the T ₁ side or T ₂ side rotates in the E direction using the shaft 18a or shaft 18b as a fulcrum by the end cam 20, the pin 32c formed on the end select lever 32 or pin 32d
Press and slide the end select lever 32 in the D direction. The convex portion 32b of the end select lever 32 slides the lock plate release lever 33 in the D direction, releasing the lock plate 59 and bringing it to a stopped state as described later.

On the other hand, as shown in FIG.
T ₂ engages with the recess 31b of the mode setting plate 31
When the continuous mode is selected in , the pin 30d of the mode select lever 30 does not press the inclined surface 32a of the end select lever 32. When the end select lever 32 is slid in the D direction at the end of tape winding, the convex portion 32b does not slide the lock plate release lever 33, and the pin 32e formed on the end select lever 32 engages the arm of the trigger lever 34. Press 34a. By this pressing, the trigger lever 34 is rotated in the E direction about the shaft 34b and disengaged from the protrusion 35a formed on the logic cam gear 35. cam gear 3
5 is rotated in the E direction. logic cam gear 3
5 has two cams 36 and 37 integrally formed on one side, and a rotational force in the E direction in the figure is applied by a starting spring (not shown), but normally,
The toothless portion 35b is locked in a position corresponding to the gear 38 rotated by the rotational drive source.

The mode select lever 30 has a built-up portion 39e formed in a shaded area in the figure when the continuous mode is selected.
7 and is pressed by the cam 37 as the logic cam gear 35 rotates at the end of tape winding. Then, the positioning pin 30c of the mode select lever 30 is inserted into the recess 31d of the mode setting plate 31.
c to switch to 1 cycle mode at _T2 . A pin 39a formed on a program interlocking lever 39 configured to be slidable in the directions of arrows A and B is brought into contact with a trapezoidal convex portion 30f formed on the side wall of the mode select lever 30 by the biasing force of a spring 40. being touched. The program interlocking lever 39 has an arm portion 39b extending toward the logic cam gear 35, and a pin 39c projecting toward the logic cam gear 35 is formed at the tip thereof.

When the logic cam gear 35 rotates at the end of tape winding in the _T2 mode, the pin 39c of the program interlocking lever 39 is connected to the logic cam gear 3.
5 is pressed against the inner surface 36a of the cam 36,
The program interlocking lever 39 is slid in the B direction. On the other hand, at the end of tape winding in continuous mode, the pin 39a of the program interlock lever 39 comes into contact with the inclined surface 30g of the mode select lever 30, and the pin 39c of the program interlock lever 39 comes into contact with the inclined surface 30g of the mode select lever 30.
Since it is sliding in the A direction more than in T ₂ mode,
When the logic cam gear 35 rotates, the pin 39c passes outside the cam 36, and the program interlocking lever 3
9 does not slide. The pin 39d formed at the left end of the program interlocking lever 39, which is slid in the B direction at the end of tape winding in the _T2 mode,
Since the arm portion 41a of the inverted L-shaped cam lock bar 41 is pressed, the cam lock lever 41 is rotated in the F direction about the shaft 41b and disengaged from the protrusion 42d formed on the program switching cam gear 42. be done.

The program switching cam gear 42 is given a rotational force in the F direction by a starting spring (not shown), is engaged with a gear 43 rotated by a rotational drive source, and is rotated in the F direction. Therefore, the cam lock lever 41 engages with the protrusion 42b of the program switching cam gear 42, and the program switching gear 4
Since the second missing tooth portion 42c moves to the position corresponding to the gear 43, the program switching gear 42 is stopped from rotating. Pin 41 of cam lock lever 41
c is a long hole 44 formed in the program lever 44
By pressing the program lever 44 in the D direction, the program switching cam gear 42 can be rotated. 45 is a program switching cam formed integrally with the program switching cam gear 42, and the switching cam 45 has an elongated hole 4.
6b and a pin 46c that engages therewith, the arm portion 46a of the program switching lever 46 is movable in directions A and B by a spring 47.
is in contact.

Shaft 46 formed on program switching lever 46
An RVS lever 48 is rotatably attached to d. The movement of the RVS lever 48 is restricted by a pin 30h formed on the mode select lever 30 that engages with a long hole 48a provided therein. Arm portion 46h of program switching lever 46
A program interlocking lever 49 that is slidable in directions A and B is attached to a pin 46e formed in , and is biased in the direction A by a spring 50. Further, the shafts 46f and 45g formed on the program switching lever 46 are provided with switching levers 51 and 4.
2 are rotatably attached to each other, and elongated holes (not shown) provided in their arm portions 51a and 52a are engaged with engagement pins 49a formed in the program interlocking lever 49, and the switching levers 51, 5
2, each movement is regulated.

Positioning pin 30 of mode select lever 30
When c is slid from the T ₂ mode to the continuous mode, the pin 30i formed on the mode select lever 30 is pressed by the arm 52b of the switching lever 52, and the positioning pin 30c is slid from the T ₂ mode to the editing mode. When the pin 30j formed on the mode select lever 30 presses the arm portion 51b of the switching lever 51, the switching levers 51 and 52 are rotated about the shafts 45f and 46q, respectively, and the program linking lever 49 is rotated about the shafts 45f and 46q.
is slid in the B direction.

10 to 16 show the sensor killer and pinch roller switching mechanism of the tape recorder in this embodiment.

FIG. 10 shows the stopped state in the editing mode. It has a program lever 44 and a pin 53a.
REC lever 53, PLAY lever 54 with pin 54a, REW lever 55 with pin 55a,
FF lever 56 with pin 56a, STOP lever 57 with pin 57a, and PAUSE lever 5
8 are attached so as to be slidable in the C and D directions in the figure, respectively, and are each biased in the C direction by a spring (not shown). Reference numeral 59 denotes a lock plate attached so as to be slidable in directions A and B, and the lock plate 59 has a spring (not shown).
The pins 5 are biased in the direction B by the
Convex portions 59a to 59d are formed at respective positions of the locking plate 59 corresponding to the levers 3a to 56a to lock the respective levers 53 to 56.

In addition, an inclined surface 59e formed on the lock plate 59
A pin 57a formed on the STOP lever 57 is projected at a position corresponding to
56 is disengaged. Furthermore, the lock plate 59
A pin 33c formed on the lock plate release lever 33 is projected at a position corresponding to the inclined surface 59f of the tape.
3c presses the inclined surface 59f, and the lock plate 59 releases each of the levers 53-56. A PAUSE operating lever 75 that rotates around a shaft 74a is in contact with the tip of the PAUSE lever 58.

The T ₁ side pinch roller lever 60, the T ₂ side FOR pinch roller lever 61, and the T ₂ side REV pinch roller lever 62 are rotatably attached to shaft supports 63 to 65, respectively, and are connected to springs 66 to 68 and pins (Fig. (not shown).
In addition, each pinch roller lever 60 to 62
During playback or recording, the roller portions 60a to 60a are
Springs 72 to 74 are attached to press 62a to capstans 69 to 71.
The _T2 side pinch roller levers 61 and 62 are formed with respective arm portions 61b and 62b for blocking or PAUSE in the _T1 mode.

Although the pinch roller levers 60, 61 and the capstans 69, 70 are shown with separate reference numerals for convenience in the description of this embodiment, they are actually coaxial.

The sub chassis 76 has a long hole 7 provided therein.
6b and the pin 76a that engages with it, C, D
The spring 77 is configured to be slidable in the direction.
is biased in the C direction. A pinch operation lever 78 is attached to the shaft 76c of the sub chassis 76.
Another pinch operation lever 79 is rotatably attached to another shaft 76d. The pinch operation levers 78, 79 have hit pins 78a, 79.
a is formed, and end surfaces 46h, 46 of the program switching lever 46 are always connected by springs 80, 81.
i is energized. The pause lever 82, which is configured to be slidable in the C and D directions, is biased in the D direction by a spring 83 and is prevented from moving in the D direction by a pin 76e of the sub-chassis 76. The pause back lever 82 includes arm portions 82a and 82b for releasing the locking of the sensor killers 84 and 85, arm portions 82c and 82d for pushing down the pinch roller levers 61 and 62 during pause, and arm portions 82c and 82d for pushing down the pinch roller levers 61 and 62 in the D direction. A convex portion 92f is formed to prevent the slide. The sensor killers 84 and 85 have shafts 84a and 85a, respectively.
The sensor lever 2 on the T 2 side is attached rotatably with the T ₂ side sensor lever 2 attached as a fulcrum, and the rotational force in the E direction is applied by the springs 86 and 87.
The arms 28c and 28d at both ends of the 8 are pressed.

The mode select lever 30 has a trapezoidal convex portion 30k formed at a position facing the arm portion 60b of the _T1 side pinch roller lever 60, and regulates the operation of the pinch roller lever 60 according to each mode. Furthermore, the arm portions 30l, 30m, and 30n formed on the mode select lever 30 are connected to the sensor killer 8.
4, 85 is disengaged. Another sensor killer 88 is rotatably attached around a shaft 88a, and a spring 86 applies a rotational force in the E direction to the arm portion 3 of the mode select lever 30.
0m, but is not pressed against the arm portion 19c of the _T1 side sensor lever 19. On the other hand, a sensor killer 90 is attached to the arm portion 19d of the sensor lever 19 so as to be rotatable about a shaft 90a as a fulcrum, and a sensor killer 90 is applied with a rotational force in the E direction by a spring 91.

Further, a slide lever 92 that is slidable in directions A and B is abutted on one end side surface 30o of the mode select lever 30 by a spring (not shown). A blocking lever 93 is rotatably attached to a shaft 92a formed on the slide lever 92. This blocking lever 93 is given a rotational force in the F direction by a spring (not shown), but is locked by the abutment pin 92b of the slide lever 92 and prevented from rotating in the F direction. At a position facing the arm portion 93a of the blocking lever 93,
A connecting lever 94 that is slidable in directions A and B is attached, and a pin 94a formed on this connecting lever 94 is in contact with an inclined surface 53b formed on the REC lever 53. REW lever 55
At the tip of the FF lever 56, there is an F/R interlocking lever 95 that can slide in the C and D directions.
6 in the C direction. When FF or
During REW, the pins 95a and 95b formed on the F/R interlocking lever 95 are slid in the D direction and press the sensor killers 90 and 85, respectively.

Next, the operating state of this embodiment will be explained for each mode based on the drawings.

(1) Edit mode time In the tape recorder according to one embodiment of the present invention, two operating states can be selected after selecting the edit mode. In other words, the playback state only on the _T1 side,
There are two so-called dubbing states in which the _T1 side plays back and the _T2 side records. First, the selection of the playback state only on the _T1 side will be explained.

1-1) Figure 11 shows T ₁ in edit mode.
This shows the playback status. Stopped state (10th
When only the PLAY lever 54 is pressed in the D direction from the figure), the sub-chassis 76 is pressed in the same direction.
At this time, the pin 54a formed on the PLAY lever 54 is locked into the convex portion 59b of the lock plate 59, and the operating state is maintained. Pinch operation levers 78, 7 attached to the sub chassis 76 at the same time
9 is also slid in the D direction. The pinch operation lever 78 comes into contact with and presses a spring 72 attached to the _T1 side pinch roller lever 60, so that the pinch roller lever 60 moves toward the shaft 6.
It is rotated in the F direction using 3 as a fulcrum. The arm portion 60b of the pinch roller lever 60 rotates without being restricted by the convex portion 30k of the mode select lever 30, and the roller portion 60a is pressed against the capstan 69. On the other hand, the pause lever 82, which is slid in the D direction by the spring 83 as the sub chassis 76 slides in the D direction, has a convex portion 82f.
comes into contact with the blocking lever 93, and the slide is stopped. Therefore, the pinch action lever 78 allows
The spring 73 is pressed and the shaft 64 is used as a fulcrum,
_T2 side pinch roller lever 6 rotated in direction F
1, rotation is restricted by the arm 61b coming into contact with the arm 82c of the pause lever 82, and the roller 61a is not pressed against the capstan 70.
Further, in the REV side pinch roller lever 62, the pinch operation lever 79 contacts the spring 74, but does not press it, and the roller portion 62a does not press against the capstan 71. Similarly, play idlers, circuits, etc. (not shown) operate, and only the _T1 side is in the playback state.

Next, the auto-stop sensor in this state will be explained.

The end detection sensor killers of the tape recorder are such that two sensor killers 88 and 90 act on the _T1 side sensor lever 19, and two sensor killers 84 and 85 act on the _T2 side sensor lever 28, respectively. It's getting old.

First, the sensor killer 88 is pressed against the arm 30m of the mode select lever 30, and the pressure on the arm 19c of the _T1 side sensor lever 19 is released. The sensor killer 90 is also pressed against the tip 76g of the sub-chassis 76 during operation, and the pressure on the arm 19c of the sensor lever 19 is released. The sensor killer 90 is also pressed against the tip 76g of the sub-chassis 76 during operation, and the pressure on the arm 19d of the sensor lever 19 is released. Therefore, at the end of tape winding, as the take-up reel cap and reel stand stop rotating, the sliding protrusion 19b of the sensor lever 19
is pressed to the maximum diameter of the swing cam 20a, then stops once, slides on the outer surface 20b of the cam 20c, and
Start end detection operation. On the other hand, a sensor killer 84 is attached to the arm 28c of the _T2 side sensor lever 28.
However, a sensor killer 85 is pressed against the arm portion 28d, and the sliding protrusion 28b of the sensor lever 28 is always disposed around the swing cam 20a. Therefore, even if the rotation of the take-up reel stand is stopped, the same sliding movement as when it is in operation is performed, so that the end detection operation is not performed.

Next, the selection of dubbing states will be explained.

1-2) FIG. 12 shows the dubbing state in the edit mode. Stopped state (10th
), press the PLAY lever 54 and the REC lever 53 in the D direction. The sub chassis 76 is slid in the D direction as described above, and the roller portion 60a of the _T1 side pinch roller lever 60 is pressed against the capster 69. On the other hand, as the REC lever 53 is pressed, the connecting lever 94 that was in contact with the inclined surface 53b
pin 94a is pressed, and the connecting lever 94 is moved to B.
direction and presses the arm portion 9a of the blocking lever 93. The blocking lever 93 is rotated in the E direction using the shaft 92b as a fulcrum. As the sub chassis 76 slides in the D direction, the spring 83
Pose back lever 82 that slides in the direction
In this case, the convex portion 82f slides without being engaged with the blocking lever 93, and the pin 76 of the sub chassis 76
It is locked at e. T ₂ side pinch roller lever 61
In this case, the arm portion 61b is rotated in the F direction without contacting the arm portion 82c of the pause lever 82, and the roller portion 61a is pressed against the capstan 70.
However, in the pinch roller lever 62, although the pinch operation lever 79 contacts the spring 74, it does not press it, and the roller portion 62a is not pressed against the capstan 71. Similarly, play idlers and circuits (not shown) operate, so play with T ₁ ,
At the same time, it enters dubbing mode to record at T ₂ .

Next, the killer of the end detection sensor in this state will be explained.

The sensor killer 90 is pressed by the tip 76g when the sub-chassis 76 slides, and the pressure on the arm 19d of the sensor lever 19 is released. Further, as the pose back lever 82 slides in the D direction, the sensor killer 84 is pressed by the arm 82a of the pose back lever 82, and the sensor killer 85 is pressed by the arm 82b.
The pressure on the arms 28c and 28d is released. In addition, the sensor killer 88 also has four sensor killers 8 because the pressure on the arm 19c of the sensor lever 29 is released when the editing mode is selected.
4, 85, 88, 90 are all sensor levers 1
The pressure on 9 and 28 has been released. Yotsute T ₁
The winding end of the tape is reached first on the side or _T2 side, and the end detection operation is started as the take-up reel cap or reel stand stops rotating.

FIG. 4 shows the mechanical configuration in the editing mode. As described above, when the end of the tape winding is reached and the sensor lever 19 or sensor lever 28 rotates in the E direction about the shafts 18a and 18b, respectively, the pin 32c or 32d formed on the end select lever 32 is rotated. Press to slide the end select lever 32 in the D direction. Therefore, the convex portion 3 of the end select lever 32
2b slides the lock plate release lever 33 in the D direction. Along with this, the lock plate release lever 3
The third pin 33c is connected to the inclined surface 59f of the lock plate 59.
Press and slide the lock plate 59 in the direction A, so that the pin 54a of the PLAY lever 54 and the REC
The pin 53a of the lever 53 is disengaged from the lock plate 59 and is in a stopped state (see FIG. 12).

Next, I will explain the sensor killer in the pause state. Note that the pause function in the tape recorder in one embodiment of the present invention is designed to work only on the _T2 side. First, in the pause operation, the PAUSE lever 58 is pressed in the D direction in the operating state shown in FIG. Since the PAUSE lever 58 presses the arm portion 75b of the PAUSE operation lever 75, the PAUSE
The operating lever 75 is rotated in the E direction about the fulcrum 75a, presses the end surface 82e of the pose back lever 82 that is in contact with the arm 75c, and slides the pose back lever 82 in the C direction. The arm portion 82c of the pause lever 82 presses the arm portion 61b of the _T2 side pinch roller lever 61 to release the pressure bond between the roller portion 61a and the capstan 70.
Furthermore, since the play idler (not shown) is also released from its crimping, only the operation of _T1 is possible. Furthermore, since the arm portions 82a and 82b of the pose buckle lever 82 are released from pressing against the sensor killers 84 and 85, each sensor killer 84 and 85 is
6 and 87, and is pressed against the arm portions 28c and 28d of the _T2 side sensor lever 28. Therefore
The state is the same as the T ₁ regeneration state, and the T ₂ side sensor lever 28 has been killed.

Next, I will explain the sensor killer during FF or REW. In the tape recorder according to one embodiment of the present invention, FF or REW operates on the _T1 side when editing mode is selected.
When the FF lever 56 or the REW lever 55 is pressed in the D direction from the stopped state shown in FIG.
The R interlocking lever 95 is slid in the D direction.
The pins 95a and 95b of the F/R interlocking lever 95 press the sensor killers 90, 85 to release the pressure on the sensor levers 29, 28. But T ₂
Since the sensor killer 84 is pressed against the arm portion 28c of the side sensor lever 28, the sensor lever 28 is killed. On the other hand, when the sensor killer 88 is selected, the pressure on the sensor lever 19 is released, so when the tape reaches the end in FF or REW and the take-up reel cap and reel stand stop rotating, the sensor killer 88 will end the tape in the same way as during playback. The detection operation will begin.

(2) In continuous mode at T ₂ Figure 13 shows the FOR operating state in continuous mode at T ₂ . Mode select lever 30
The positioning pin 30c is engaged with the recess 31b of the mode setting plate 31. When the PLAY lever 54 is pressed in the D direction from the stopped state, the sub-chassis 76 is pressed in the same direction. A pin 54a formed on the PLAY lever 54 is locked into a convex portion 59b of the locking plate 59 to maintain the operating state. Pinch operation lever 7 attached to sub chassis 76 at the same time
8 and 79 also slide in the D direction. The pinch operation lever 78 contacts and presses a spring 72 attached to the _T1 side pinch roller lever 60, so that the pinch roller lever 60 moves toward the shaft 63.
It is rotated in the F direction using the fulcrum as the fulcrum. However, the arm portion 60b of the pinch roller lever 60 comes into contact with the convex portion 30k of the mode select lever 30, and rotation in the F direction is restricted, so the roller portion 60a is not pressed against the capstan 69. On the other hand, when the continuous mode is selected at _T2 , the slide lever 92 comes into contact with the recess 30p of the mode select lever 30, so that it slides in the B direction compared to the editing mode. Further, as the select lever 30 slides, the blocking lever 93 also slides in the direction B, so that the pause lever 82 has a convex portion 82f on the blocking lever 93.
It is sliding in the D direction without being engaged with 3. The pinch roller lever 61 is pressed by the spring 73 by the pinch operation lever 78 and rotated in the direction F using the shaft 64 as a fulcrum. The portion 61a is the capstan 70
is crimped. However, although the pinch operation lever 79 of the pinch roller lever 62 comes into contact with the spring 74, it does not press the spring 74, and the roller portion 62a is not pressed against the capstan 71. Similarly, play idlers and circuits (not shown) operate and the _T2 side
FOR operation status is established.

Next, the switching operation from FOR to REW and the REW
Explain the operating status of. FIG. 5 shows the mechanical configuration of the FOR state in continuous mode at _T2 . When the end of the tape winding is reached in this state, the sensor lever 28 is moved to the shaft 18 by the end cam 20.
It is rotated in the E direction using b as a fulcrum. The pin 32d formed on the sensor lever 32 is pressed in the D direction to slide the end select lever 32 in the same direction. At this time, the convex portion 32b of the end select lever 32 is connected to the pin 33a of the lock plate release lever 33.
The lock plate release lever 33 is not in the position to engage with the lock plate release lever 33.
It will never work. On the other hand, since the pin 32e formed on the end select lever 32 presses the arm 34a of the trigger lever 34, the trigger lever 34 is rotated in the E direction about the shaft 34b, and the protrusion formed on the logic cam gear 35 The engagement with the portion 35a is released. The logic cam gear 35 is rotated in the E direction by a starting spring (not shown), meshes with the gear 38, and the cam 36
It is also rotated in the E direction. The pin 39a of the program interlocking lever 39 is the mode select lever 3
0, and the pin 39c of the program interlocking lever 39 is positioned so as to slide on the inside 36a of the cam 36 when the logic cam gear 35 rotates.
As the program interlocking lever 39 rotates, the pin 39c of the program interlocking lever 39 is pressed against the inside 36a of the cam 36, and the program interlocking lever 39 is slid in the B direction. Therefore, since the pin 39d formed on the program interlocking lever 39 presses the arm portion 41a of the cam lock lever 41, the cam lock lever 41
is rotated in the F direction about the shaft 41b, and is disengaged from the protrusion 42a formed on the program switching cam gear 42. Therefore, the program switching cam gear 42 is equipped with a starting spring (not shown).
is rotated in the F direction by the cam 43, and is engaged with the gear 43, and is rotated in the F direction together with the program switching cam 45. Accordingly, the program switching lever 46 that is in contact with the program switching cam 45 is slid in the direction B by the spring 47. At this time, the program switch attached to the program switching lever 46
The RVS lever 48 is the end select lever 32
This prevents the pin 32f formed in the pin 32f from being pressed.

FIG. 14 shows the operating state of REV. When the program switching lever 46 slides in the B direction, the left inner end surface 46 of the program switching lever 46
The contact pin 79a of the pinch operation lever 79, which had been biased at i, is pressed in the same direction and rotated in the E direction about the shaft 76b. Pinch action lever 7
9 presses a spring 74 attached to the pinch roller lever 62. The pinch roller lever 62 is rotated in the E direction about the shaft 65, and the roller portion 62a is pressed against the capstan 71.
On the other hand, as the program switching lever 46 slides in the B direction, the pinch operation lever 78 is rotated by the spring 80 in the E direction about the shaft 76c, releasing the pressure on the spring 73 attached to the pinch roller lever 61. From roller part 6
1a is released from being crimped onto the capstan 70.
At the same time, a play idler, a circuit, etc. (not shown) operate, and the REV operation state is established.

FIG. 6 shows the mechanism configuration in the REV state.
When the end of tape winding is reached in this state, the end select lever 32 is slid in the D direction as described above, but the convex portion 32b does not operate the lock plate release lever 33. On the other hand, the pin 32e is the trigger lever 3
Press 4 to rotate the logic cam gear 35. The pin 39c of the program interlocking lever 39 slides on the inner side 36a of the cam 36 and is pressed, whereby the program interlocking lever 39 is slid in the direction B, and the engagement between the cam lock lever 41 and the program switching cam gear 42 is released. do. Therefore, since the program switching cam gear 42 is rotated in the F direction, the program switching lever 46 is pushed in the A direction. As the program lever 46 slides, the pinch operation levers 78 and 79 are rotated, and the roller portion 61a of the FOR side pinch roller lever 61 is pressed against the capstan 70.
Roller part 62 of REV side pinch roller lever 62
The press contact between a and the capstan 71 is released, and the operation is switched to the FOR operation shown in FIG. 13 described above.

As mentioned above, in continuous mode at T ₂ ,
After the FOR, REV operation, the end select lever 32 is slid by the rotation of the sensor lever 28, the logic cam gear 35 is rotated, the program switching cam gear 42 is rotated via the program interlocking lever 39, and the program switching lever 4 is rotated.
Slide 6. And pinch action lever 7
By switching between 8 and 79, continuous playback of FOR and REV is performed.

Next, the killer of the termination detection sensor in this mode will be explained.

FIG. 13 shows the operating state in one cycle mode at _T2 . When this mode is set with the mode select lever 30, the sensor killer 84 is pressed by the arm 30n of the mode select lever 30 and is rotated in the direction F using the shaft 84a as a fulcrum. The pressure is released. On the other hand, the sensor killer 88 does not press the arm portions 30l, 30m of the mode select lever 30, but presses the arm portion 19c of the sensor lever 19. During operation, the sensor killer 20 is connected to the tip 76g of the sub-chassis 76, and the sensor killer 85 is connected to the sensor lever 19, by the arm 82b of the pause lever 82, respectively.
The pressure on 28 is released. Therefore, the _T1 side sensor lever 19 is locked, and the _T2 side sensor lever 28 is turned off.
Therefore, at the end of winding the tape, as the take-up reel stand stops rotating, the sensor lever 28
The end select lever 32 is rotated and the end select lever 32 is slid to start the switching operation.

Next, I will explain the sensor killer in the pause state. As before, press the PAUSE lever 58 in the D direction and slide the PAUSE back lever 82 in the C direction to enter the pause state. Pose back lever 8
Since the arm portion 82b of the sensor lever 28 is no longer pressed against the sensor killer 85, the sensor killer 85 is rotated in the direction E using the shaft 85a as a fulcrum by the spring 87. Therefore, the switching operation will not start during pause. Also, during FF or REW, the sensor killers 90 and 85 are
The sensor levers 19 and 28 are connected by the interlocking lever 95.
The pressure on is released. Further, the sensor killer 84 is released from being pressed against the arm portion 28c of the sensor lever 28, and the sensor killer 88 is pressed against the arm portion 19c of the sensor lever 19. Therefore
The _T1 side sensor lever 19 is locked, and the _T2 side sensor lever 28 is turned off. Therefore, at the end of winding the FF or REW tape, the sensor lever 28 rotates as the take-up reel stand stops rotating, and the end select lever 32 slides in the D direction. Although not shown, FF or REW can be used in _T2 mode.
When the lever is pressed, the end select lever 32 is pushed in the E direction and the convex portion 32b is rotated to a position opposite to the pin 33a of the lock plate release lever 33, so when the end select lever 3 slides, the lock is released. The plate release lever 33 is slid to a stopped state.

(3) In 1 cycle mode at T ₂ Figure 15 shows in 1 cycle mode at T ₂
Indicates FOR operating status. The positioning pin 30c of the mode select lever 30 is connected to the mode setting plate 3.
It engages with the recess 31c of No. 1. From a stopped state
When the PLAY lever 54 is pressed in the D direction, the sub-chassis 76 is pressed in the same direction. At the same time, the pinch operation levers 78 and 79 are also slid in the D direction, and the pinch operation lever 78 is moved to the _T1 side pinch roller lever 6.
0 and rotates the pinch roller lever 60 in the F direction. However, the arm portion 60b of the pinch roller lever 60 comes into contact with the convex portion 30k of the mode select lever 30 and rotation in the F direction is restricted, so the roller portion 60a is not pressed against the capstan 69. On the other hand, when the one-cycle mode is selected at _T2 , the slide lever 92 comes into contact with the recess 30p of the mode select lever 30, so that it is slid in the B direction similarly to the continuous mode at _T2 . Further, since the blocking lever 93 is also slid in the B direction, the pull lever 82 is slid in the D direction without the convex portion 82f being engaged with the blocking lever 93. The spring 73 is pressed against the pinch operation lever 78,
The pinch roller lever 61 rotated in the F direction is
The arm portion 61b is the arm portion 82 of the pose back lever 82.
The roller portion 61a rotates without contacting the capstan 70, and the roller portion 61a is pressed against the capstan 70. However, although the pinch operation lever 79 of the pinch roller lever 62 comes into contact with the spring 74, it does not press the spring 74, and the roller portion 62a is not pressed against the capstan 71. Similarly, play idlers and circuits (not shown) operate, and the _T2 side enters the FOR operation state.

Next, the switching operation from FOR to REV and the operating state of REV will be explained. FIG. 7 shows the mechanical configuration of the FOR state in the 1-cycle mode at _T2 . When the tape ends in this state,
As in the continuous mode at _T2 , the end select lever 32 is slid in the D direction, presses the trigger lever 34, and switches the logic cam gear 35.
Rotate. The pin 39c of the program interlocking lever 39 slides on the inside 36a of the cam 36 in the direction B, and presses the cam lock lever 41. Therefore, the program switching cam gear 42 is rotated in the F direction, and the program switching lever 46 is slid in the B direction. At this time, the RVS is attached to the program switching lever 46 and positioned by the pin 30h of the mode select lever 30.
The lever 48 is also slid in the direction B, and comes into contact with the pin 32f formed on the end select lever 32 facing in the sliding direction, and reaches a position where the convex portion 32b of the end select lever 32 is engaged with the pin 33a of the lock plate release lever 33. to press. As in the continuous mode at T ₂ , the pinch operation levers 78 and 79 are rotated as the program switching lever 46 slides to release the pressure between the roller portion 61a of the FOR side pinch roller lever 61 and the capstan 70, and the REV side pinch roller The roller portion 62a of the lever 62 is pressed onto the capstan 71. The play idler, circuit, etc. are also switched, and the T ₂ side REV
It becomes operational.

Figure 8 shows the mechanism configuration in the REV state. When the tape ends in this state, the end select lever 32 is slid in the D direction as described above. For this reason, the convex portion 32b formed on the end select lever 32 presses the pin 33a of the lock plate release lever 33, thereby releasing the lock plate release lever 33.
slide in the D direction to disengage the lock plate 59 and the PLAY lever 54 and stop the operation.

As mentioned above, in the 1 cycle mode at _T2 , when switching from FOR to REV, the end select lever 32 is pressed by the RVS lever 48 attached to the program switching lever 46, and after REV operation,
As the end select lever 32 slides, the lock plate release lever 33 is slid to a stopped state.

Next, the killer of the termination detection sensor in this mode will be explained.

FIG. 15 shows the operating state in one cycle mode at _T2 . Mode select lever 3
When this mode is set at 0, the sensor killer 84 is pressed against the arm 30n of the mode select lever 30, and the pressure on the arm 28c of the sensor lever 28 is released, as in the continuous mode at _T2 . On the other hand, the sensor killer 88 is not pressed by the arms 30l and 30m of the mode select lever 30, and the sensor killer 88 is not pressed by the arms 1 and 1 of the sensor lever 19.
It is pressed to 9c. During operation, the sensor killers 90 and 85 are released from being pressed against the sensor levers 19 and 28, respectively, as described above. Therefore, since the _T1 side sensor lever 19 is killed and the _T2 side sensor lever 28 is released, at the end of the tape winding, the sensor lever 2
8 is rotated to start the switching operation. Also, the sensor killer in the pause state, FF or REW state is the same as in the continuous mode in _T2 described above, so the explanation will be omitted.

(4) In continuous mode Figure 9 shows the operating status in continuous mode. Positioning pin 3 of mode select lever 30
0c is engaged with a recess 31d of the mode setting plate 31. Further, the slide lever 92 is in contact with the end surface 30o of the mode select lever 30. When the PLAY lever 54 is pressed in the D direction from the stopped state, the sub-chassis 76 is slid in the same direction. The pinch operation lever 78 presses a spring 72 attached to the _T1 side pinch roller lever 60, and rotates the pinch roller lever 60 in the F direction. The arm portion 60b of the pinch roller lever 60 is
The mode select lever 30 is rotated without being restricted by the convex portion 30k, and the roller portion 60a is pressed against the capstan 69. On the other hand, sub chassis 7
The pose buckle lever 82 is slid in the D direction by the spring 83 along with the slide of step 6.
The convex portion 82f comes into contact with the blocking bar 93 and the sliding is stopped. Therefore, the pinch action lever 78
The spring 73 was pressed and rotated in the F direction.
The rotation of the T ₂ side pinch roller lever 61 is restricted by the arm portion 61 b coming into contact with the arm portion 8 c of the pause back lever 82 , and the roller portion 61 a is not pressed against the capstan 70 . Further, in the REV side pinch roller lever 62, the pinch operation lever 79 contacts the spring 74, but does not press it, and the roller portion 62a does not press against the capstan 71. At the same time, play idlers, circuits, etc. (not shown) operate, and the _T1 side enters the playback state.

Next, the switching operation from T ₁ to T ₂ will be explained.
FIG. 9 shows the mechanical configuration in continuous mode.
When the end of the tape winding is reached in this state, the end select lever 32 is slid in the D direction as described above, but the convex portion 32b does not press the pin 33a of the lock plate release lever 33. On the other hand, the pin 32e presses the trigger lever 34 and the logic cam gear 3
Rotate 5. A cam 37 formed in the logic cam gear 34 presses the built-up portion 30e of the mode select lever 30 to a position opposite to the one-cycle mode of _T2 . That is, the positioning pin 30c of the mode select lever 30 is slid from the protrusion 31d of the mode setting plate 31 to the protrusion 31c. As described above, the convex portion 30k of the slid mode select lever 30 is T ₁
The arm portion 60b of the side pinch roller lever 60 is pressed to release the pressure bond between the roller portion 60a and the capstan 69. On the other hand, when the slide lever 92 comes into contact with the convex portion 30p of the mode select lever 30, the engagement between the blocking lever 93 and the convex portion 82f of the pause back lever 82 is released. Therefore, the arm portion 61b of the _T2 side pinch roller lever 61 is no longer restricted by the arm portion 82c of the pause back lever 82 and rotates in the F direction, so that the roller portion 61a is pressed against the capstan 70. Furthermore, when the logic cam gear 35 rotates, the program interlocking lever 39
Since the pin 39c passes outside the cam 36, the program interlocking lever 39 does not slide. In addition, a play idler, a circuit, etc. (not shown) operate, and the 1-cycle mode FOR state at _T2 described above (FIG. 15) is established. Thereafter, it switches to REV at the end of FOR tape winding, and stops at the end of REW winding.

Next, the killer of the termination detection sensor in this mode will be explained.

FIG. 16 shows the operating state in continuous mode. When this mode is set using the mode select lever 30, the sensor killer 88 is pressed by the arm portion 30l of the mode select lever 30, and the press against the arm portion 19c of the sensor lever 19 is released. Further, the sensor killer 90 is also pressed against the tip 76g of the sub-chassis 76 during operation, and the pressure on the arm 19d of the sensor lever 29 is released. Therefore, at the end of tape winding, the switching operation is started as the take-up reel cap and reel stand stop rotating. On the other hand, the arm portion 28c of the sensor lever 28
The sensor killer 84 is pressed against the arm portion 28d, and the sensor killer 85 is pressed against the arm portion 28d, and the switching operation is not performed because the same sliding motion as during operation is applied regardless of the rotation of the take-up reel stand. Not possible.

Next, I will explain the sensor killer during FF or REW. In addition, in the tape recorder according to an embodiment of the present invention, when continuous mode is selected, FF or
REW is designed to work on the _T1 side. When the FF lever 56 or the REW lever 55 is pressed in the D direction from the stopped state, the F/R interlocking lever 95 is slid in the same direction, the pins 95a and 95b press against the sensor killers 90 and 85, respectively, and the sensor lever 19 and The pressure on 28 is released.
However, since the sensor killer 84 is pressed against the arm 28c of the _T2 side sensor lever 28, the sensor lever 28 is killed. On the other hand, sensor killer 88 is sensor lever 1 when mode is selected.
The pressure on 9 has been released. Furthermore, FF lever 5
6 or REW lever 55 is pressed, the end select lever 32 is pressed in the E direction and the convex portion 32d is rotated to a position opposite to the pin 33a of the lock plate release lever 33, so that the FF or REW lever 55 is pressed.
At the end of winding the REW, when the end select lever 32 slides, the lock plate release lever 33 slides and comes to a stopped state.

(G) Effects of the Invention According to this invention, the first and second sensor levers are rotated in sliding contact with the rocking cam of the same rotary body, and the tape end point in the first or second tape mode is Since the end is detected by the sensor lever on the selected side, the end detection device of the duplex tape recorder has a simple configuration.
The end of the tape can be detected.

[Brief explanation of the drawing]

Figures 1 to 16 are drawings showing one embodiment of the present invention, with Figure 1 being a vertical sectional view of the main parts showing the arrangement when the cassette tape is installed, and Figure 2 being a front view showing the operation button part. Figures 3a and 3b are a longitudinal sectional view and a plan view of the main parts showing the auto-stop sensor section, and Figures 4 to 9 show the mechanism configuration. Figure 5 shows the FOR state in continuous mode at T ₂ , Figure 6 shows the REV state in continuous mode at T ₂ , Figure 7 shows the FOR state in 1 cycle mode at T ₂ , and Figure 8 shows the 1 at T _2. REV status in cycle mode, 9th
The figure shows the continuous mode, Figures 10 to 16 show the sensor killer and pinch roller switching mechanism, Figure 10 shows the stopped state in the edit mode, and Figure 11 shows the _T1 playback in the edit mode. Status, Figure 12 is dubbing status in edit mode, Figure 13 is FOR in continuous mode at T ₂
Figure 14 shows the REV reproduction status in continuous mode at T ₂ , Figure 15 shows the FOR reproduction status in 1 cycle mode at T ₂ , and Figure 16 shows the reproduction status in continuous mode. be. 1, 2...Cassette tape, 3, 4...Capstan, 6, 8, 9...Pinch roller, 11...
Take-up reel cap, 15a, 25a...Press projection, 19,28...Sensor lever, 19b, 2
8b...Sliding protrusion, 20...End cam, 20a
...Swinging cam, 20c...cam.

Claims (1)

[Claims] 1. Two cassette tapes, the first and second, are
These cassette tapes are stacked and stored in two tape storage units, and one capstan shaft is associated with these cassette tapes, and first and second pinch rollers corresponding to the first and second cassette tapes are respectively associated with the corresponding capstan shaft. First, by touching
In a duplex tape recorder that selectively runs a second cassette tape at a constant speed, a rotating body including an eccentric swing cam and a drive cam and driven by an appropriate drive source is provided with a rotating body that slides between the swing cam and the drive cam. A first sensor lever with a sliding protrusion that can be contacted is provided so as to be able to rotate and swing, and a sensor lever that receives the rotational force of the reel cap and cooperates with the swing cam on the side of the reel cap to which the first cassette tape is attached. and a push means for rotationally swinging the first sensor lever, and the first sensor lever is actuated by the swing cam and the push means while the reel cap is rotating. The means is rotated and swung within a range that does not apply any acting force, and a second sensor lever that is provided with a sliding protrusion that can come into sliding contact with the oscillating cam and the drive cam of the rotating body is rotatably oscillated. The second sensor lever is provided on the reel stand side on which the second cassette tape is attached, and receives the rotational force of the reel stand via a connecting member such as a gear, and works with the swing cam to rotate and swing the second sensor lever. A pushing means is provided to cause the second sensor lever to rotate and oscillate within a range in which no acting force is applied to the actuated means by the swinging cam and the pushing means while the reel stand is rotating. At the end of the tape in the first or second tape mode, when the reel cap or reel stand on the selected side stops rotating, the reel cap or reel stand on the side that has stopped rotates and oscillates. After the first or second sensor lever is brought by the action of the swinging cam so that the sliding protrusion of the sensor lever is positioned at the top dead center of the swinging cam, the sliding protrusion is moved by the driving cam. What is claimed is: 1. A terminal end detection device for a duplex tape recorder, characterized in that it is configured to be driven and to apply an acting force to actuated means by each sensor lever.