JP3318806B2 - Tape end detection device for tape drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape end detecting device for a tape drive such as a cassette tape recorder.

[0002]

2. Description of the Related Art Generally, a tape player such as a cassette tape recorder is provided with a tape end detecting device for detecting the end of the tape when the winding of the tape is completed. There is a configuration in which the tape running direction is reversed or the tape running direction is reversed. As such a tape end detecting device, there is a device configured as shown in FIG.

This tape end detecting device includes an eccentric cam 31a provided on a rotating body 31 which is rotated in a frictional engagement with a reel base.
And a projection 31b are formed, and the projection 31b is an eccentric cam 31a.
And a slip lever 32 frictionally engaged with the reel base on the same axis as the rotating body 31. ing.

[0004] A first detecting member 33 is arranged corresponding to the operating surface of the rotating body 31 on which the eccentric cam 31a and the projection 31b are formed, and is rotatably supported by a shaft 34 at a central portion thereof. engaging projections 33a ₁ formed at the tip parts 33a are in correspondence with the peripheral surface of the eccentric cam 31a, also the engaging piece 33a ₂ is engaged with the slip lever 32 is projected on one half 33a side ing.

A second detecting member 35 is supported by a shaft 36 at a bearing portion 35a corresponding to the distal end of the other end portion 33b of the first detecting member 33. Is the engagement piece 3 with which the first detection member 33 is engaged.
5b and an engaging edge 35c corresponding to an engaging projection 38a protruding from a capstan wheel 38 of a capstan 37 as a rotary drive mechanism.
A pressing arm portion 35d and a return spring piece 35e are formed to protrude from a. The pressing arm 35d of the second detecting member 35 corresponds to the lock plate 39 of the operation lever.

As described above, the tape end detecting mechanism constituted by the respective members generates a predetermined friction torque on the slip lever 32 while the reel base is rotating and the tape is running, so that the slip lever 32 has a first frictional torque. by first detecting member 33 is rotationally urged in engagement via the engagement piece 33a _2, engagement projections 33a ₁ of the tip comes into contact with the circumferential surface of the eccentric cam 31a of the rotary member 31, the first The first detecting member 33 is swung by the rotation of the rotating body 31 following the eccentric cam 31a.

When the reel base stops at the end of the tape from the tape running state, the torque of the slip lever 32 is not generated.
Ready to be stopped at the position pressed by the maximum diameter of 1a, by rotation of the rotating body 31 is continued in this state, the outer projection 31b is engaged with the engagement projections 33a ₁ of the tip As a result, the first detecting member 33 is rotationally displaced more than when it is pushed by the maximum diameter portion of the eccentric cam 31a.

[0008] Due to the rotational displacement of the first detecting member 33, the tip of the other half portion 33b engages with the engaging piece 35b of the second detecting member 35 and presses it. The member 35 is rotated and displaced so that the engagement edge 35c faces the locus of the engagement protrusion 38a of the capstan wheel 38, and is pressed by the engagement protrusion 38a as the capstan wheel 38 rotates. As a result, the second detection member 35 is largely rotated and displaced, and the pressing arm 35d pushes and slides the lock plate 39 to unlock the operation lever.

As described above, the conventional tape end detecting mechanism is configured to detect the end of the tape and release the lock in the operating state of each mode operating lever.

[0010]

In the conventional tape end detecting mechanism constructed as described above, the first detecting member keeps the tape end even after the automatic unlocking of each mode operation lever and the stop operation are completed. Is detected, that is, it remains in a state of being largely rotated and displaced by the projection of the rotating body, so that the mode operation lever cannot be locked at the next quick push button operation, and the push button is pressed at a normal speed. Even when operated, the rotating body rotates and the engaging projection of the capstan wheel engages with the engaging edge of the second detecting member until the engaging projection of the first detecting member comes off the projection of the rotating body. This causes chattering noise.

Another disadvantage is that a timer standby mechanism cannot be added.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a tape end detecting device of a tape driving device in which a detecting member is returned to a position at the time of running or stopping the tape after detecting the end of the tape. The purpose is to do.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a rotating member having a cam and a projection, which is rotated in a frictional engagement with a reel base. A first detection member that is displaced from the cam side of the rotating member and engages with the projection to detect the end of the tape; and a first detection member that is displaced when the tape ends and is displaced by being engaged with the drive mechanism. In the tape end detecting device of the tape drive device having another detecting member displaced by the first detecting member, the other detecting member is engaged with the first detecting member in the range of the displacing operation range of the other detecting member. Forming a portion, after the tape end detection, the other detection member in the first detection member,
The first engaging member is disengaged from the projection of the rotating member by interference engagement via the engaging portion, and is returned to the position at the time of tape running or at the time of stopping.

[0014]

According to the device of the present invention, the rotating member continues to rotate even when the reel stand is stopped due to the end of the tape, so that the first detecting member is projected from the cam side with respect to the rotating member. The first detection member is displaced so as to be engaged, and the other detection members are also displaced following the displacement of the first detection member. The other detection members are greatly displaced by the drive mechanism by this displacement, and the end of the tape is detected. And the engaging portion interferes with the first detecting member to disengage the first engaging member from the projection of the rotating member and return to the position at the time of tape running or stop, and Prepare for operation.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an exploded perspective view of a part of a transport in a tape player as an example of a tape driving apparatus to which the present invention is applied, FIG. 2 is an exploded perspective view of the same back side, and FIG. In a plan view on the back side of the device,
1 to 3, 1 is a mechanical chassis, 2 is a supply-side reel stand, 3 is a take-up reel stand, 4 is a capstan,
Reference numeral 5 denotes a capstan wheel fixed to the lower end of the capstan 4.

The supply-side reel base 2 is supported by a bearing 6 projecting from the front side of the mechanical chassis 1 via a compression coil spring 7, and the take-up reel base 3 is also mounted on the front side of the mechanical chassis 1. The two reel stands 2 and 3 are integrally provided with reel gears 2a and 3a on the outer peripheral portions thereof.

A slip lever 9 is coaxially and rotatably mounted at the lower end of the take-up reel base 3, and a friction member (not shown) such as a compression spring interposed between the take-up reel base 3 and the reel base 3. The rotation of the reel base 3 is transmitted by frictional force.

The capstan 4 is supported by a bearing 10 provided from the front side to the back side of the mechanical chassis 1,
The capstan wheel 5 is located on the back side of the mechanical chassis 1, and is engaged with the upper surface of the capstan wheel 5, that is, near the center of the surface facing the back side of the mechanical chassis 1 as shown in FIG. A projection 5a is provided.

Each operating lever 11 is disposed on the front side of the mechanical chassis 1, and a lock plate 12 is disposed so as to be able to reciprocate in a direction orthogonal to the operating direction of each operating lever 11. As is well known, each of the operation levers 11 and the lock plate 12 are provided with a lock pin 13 projecting from each of the operation levers, and an engagement window 1 formed in the lock plate 12.
2a (see FIG. 3), and by turning on the operation lever, the lock pin 12 is locked to the engagement window 12a of the lock plate 12;
In the forward direction, that is, by pushing the engagement end portion 12b by a lock release mechanism described later and sliding in the lock release direction, the lock of the lock pin 13 by the engagement window 12a is released, and the operation lever is moved. It is to be restored.

As shown in FIGS. 2 and 3, a tape end detection / shutoff mechanism 14 is provided on the rear side of the mechanical chassis 1, and the tape end detection / shutoff mechanism 14 includes a rotating member. 15, a detection lever 16 as a first detection member and a detection member 17 as a second detection member.

The rotating member 15 includes an eccentric cam (disc cam) 15b eccentric from the center hole 15a and an eccentric cam 15b.
b, the largest diameter portion 15b of the eccentric cam 15b
Located outside on the _first trajectory is constituted by forming a projecting cam 15c, the ends 15c ₁ of the protruding cam 15c is an inclined surface. The rotating member 15 is rotatable with respect to each other by inserting a rotating shaft 18 into a center hole 15a. A friction member 20 such as a compression spring is interposed between the rotating member 15 and a flange washer 19 attached to a lower end of the rotating shaft 18. Thus, the rotation of the rotating shaft 18 is transmitted by the friction of the friction member 20.

The rotating shaft 18 is inserted from the back side of the mechanical chassis 1 into the tubular bearing 8 on which the above-mentioned take-up reel base 3 is pivotally supported, and is engaged with the take-up reel base 3. 3 and is integrally rotated.

As shown in FIGS. 3 and 4, the detection lever 16 is formed in a substantially rectangular shape, and is rotatable by being inserted into a support shaft 21 erected on the rear surface of the main chassis 1 at a central bent portion. The one half 16a is supported so as to face the lower surface side of the rotating member 15, that is, the operating surface side, and the other half 16b is positioned on the capstan wheel 5 side. large diameter recess of the bearing portion 16c is continuous inner circumferential side to the shaft hole 16c ₁ substantially half portion of the one half portion 16a side in a short cylindrical shape having a shaft hole 16c ₁ having substantially the same diameter as the support shaft 21 in the notch shape of It is formed on the relief portion 16c ₂ which was. The upper surface side of the half portion 16a of the detection lever 16, i.e., on the side facing the operating surface of the rotating member 15, the engaging projection 16a ₁ opposite to the circumferential surface of the eccentric cam 15b and the protruding cam 15c Yes protruding formation, also, the other half portion 16b side, lower side, i.e., the engagement flange portions 16b ₁ which engages the detection member 17 on the side of the direction opposite to the projecting direction of the engagement projection 16a ₁ There are protruded, the edges of the engagement flange portions 16b ₁ side is inclined guide surface 16b ₂ are formed by notch in an L-shape, furthermore, contrary to the guide surface 16b ₂ of the other half 16b side the ends of the side edges pressing projection 16b ₃ are protruded.

The detection lever 16 has an upper surface near the half-portion 16a from the central shaft support, that is, the mechanical chassis 1
An engagement piece 16d is provided upright on the surface opposite to the back surface of the mechanical chassis 1 to guide the mechanical chassis 1 through a guide through hole 22 formed in the mechanical chassis 1.
And is engaged with the above-mentioned slip lever 9.

The detection lever 16 is located on the upper surface side near the other half 16b from the central shaft support, that is, the mechanical chassis 1
A compression coil spring 23 is fitted on the surface opposite to the back surface of the mechanical chassis 1 and is brought into contact with the back surface of the mechanical chassis 1.
The b-side is constantly biased in a direction away from the rear surface of the mechanical chassis 1.

Thus, the detection lever 16 is connected to the bearing 1
Other half 16b side half portion support shaft 21 of 6c shaft hole 16c ₁ of
, And is held parallel to the mechanical chassis 1 (see FIG. 4).

As shown in FIGS. 2 and 3, the detecting member 17 is located at the end of the other half 16b of the detecting lever 16 and is pivotally supported. The detection member 17 is horizontally moved from a short cylindrical bearing portion 17a which is inserted into a support shaft 24 protrudingly provided on the back surface side of the main chassis 1 in the other half 1 of the detection lever 16.
A first engagement piece 17b and a second engagement piece 17c are formed on opposite ends of the first engagement piece 17b so as to be sandwiched from both sides. engaging the inclined surface 17b ₁ which corresponds to the inclined guide surface 16b ₂ are formed, the side edge portion of the first engagement piece 17b side corresponding to the engaging projection 5a of the capstan wheel 5 described above A mating portion 17d is formed.

The detecting member 17 has the pressing arm 17e of the lock plate 12 projecting from the bearing 17a in a direction substantially perpendicular to the direction in which the first and second engaging pieces 17b and 17c are formed. The return spring piece 17f is formed integrally with the bearing 17a so as to extend therefrom.

The detecting member 17 has a bearing 17a inserted into and supported by a support shaft 24, and a distal end of a return spring piece 17f is elastically attached to a locking projection 25 projecting from the rear side of the mechanical chassis 1. , The first and second engagement pieces 17b and 17c are always positioned with the end of the other half 16b of the detection lever 16 interposed therebetween, and the engagement edge The rotation is restricted by a rotation restricting projection 26 protruding from the rear side of the mechanical chassis 1 so that 17d is located away from the rotational path of the engaging projection 5a of the capstan wheel 5. I have. The pressing arm portion 17e is separated from the engaging end portion 12b of the lock plate 12 at a required interval in a state where the rotation of the detecting member 17 is restricted.

Next, the operation of the tape end detecting / shutoff mechanism 14 configured as described above will be described with reference to FIGS.

First, during tape reproduction or recording, the supply-side reel base 2 is rotatable, and the take-up reel base 3 is rotated by a rotational force transmitted from a drive mechanism (not shown). By the rotation of the member 15, the rotating shaft 18 is rotated via the friction member 20, and is rotated integrally with the rotating shaft 18 to take up the tape. At this time, the slip lever 9 is also rotated by the friction member (not shown). , And is rotated integrally with the take-up reel base 3 (in the direction of arrow a).

In this state, the detection lever 16 is urged to rotate by the slip lever 9 via the engagement piece 16d by the slip lever 9 as shown in FIG. 4 (see FIG. 4), the engagement protrusion 16 a ₁ of the half part 16 a is brought into contact with the peripheral surface of the eccentric cam 15 b of the rotating member 15. In this state, the detection lever 16 moves with the rotation of the rotating member 15,
The tape rotates and follows the eccentric cam 15b, and the tape continues to run due to the rotation of the take-up reel base 3.

In this way, the tape is run to the end and stretches between the two reel bases 2 and 3,
When the take-up reel base 3 stops, the slip lever 9 also stops, and no rotational urging force is applied to the detection lever 16.

In this state, the rotating member 15 continues to rotate in a slip relationship with respect to the take-up reel base 3.
Therefore, by the eccentric cam 15b to the engaging projections 16a ₁ of the detection lever 16 slides toward the large diameter portion 15b ₁ from the small-diameter portion, the detection lever 16 around the fitting portion of the bearing portion 16c for supporting shaft 21 The eccentric cam 15b is rotated horizontally in the clockwise direction (the direction of arrow c), and the maximum diameter portion 15b ₁
There once clockwise rotation in a state of sliding contact with the engagement projection 16a ₁ is stopped, as shown in FIG. 5, the engaging projection 16a ₁ are located so as to face the protruding cam 15c away from the eccentric cam 15b You.

When the rotating member 15 further rotates in this state, the projection cam 15c is brought into contact with the engagement projection 1 of the detection lever 16.
It abuts the 6a _1, is engaged in sliding contact engagement with the outer peripheral surface of the protruding cam 15c press the engaging projections 16a ₁ in the outer peripheral direction along the inclined surface of the end portion 15c _1. This allows the detection lever 16
As shown in FIG. 6, is further rotated in the clockwise direction other half 16b is detected via the pressing projection 16b ₃ members 1
7, the second engaging projection 17c is pressed, and the detection member 17 is supported by the support shaft 24 against the urging force of the return spring piece 17f.
The inclined surface 17b ₁ of the first engagement piece 17b is corresponding to the inclined guide surface 16b ₂ of the detection lever 16 is rotated in the counterclockwise direction (direction of the arrow d) around the fitting portion of the bearing portion 17a for At the same time, the engaging edge 17d faces on the rotation locus of the engaging protrusion 5a protruding from the capstan wheel 5.

In this state, the detecting member 17 is
The engaging projection 5a of the capstan wheel 5 is engaged with the cap d, and is rotated counterclockwise (direction of arrow d) to the position shown in FIG. The first engaging piece 17b rides on the back side of the end of the other half 16b of the detection lever 16, that is, the detection lever 16 is engaged with the other half 16b in the vertical direction.
The b side is pressed toward the rear surface of the mechanical chassis 1.

By this pressing, the detection lever 16 is moved as shown in FIG.
As shown in the figure, the compression coil spring 23, which has been kept in a horizontal state, is compressed, and is inclined such that the other half 16b approaches and the one half 16a separates from the back side of the mechanical chassis 1, engagement projection 16a ₁ is rotary member 15
Is moved so as to be displaced from the protruding cam 15c in the height direction. The tilting operation of the detection lever 16 is performed by the bearing 1.
Approximately half portion of one half 16a side to 6c, since is formed with relief portions 16c ₂ that the recess of large diameter contiguous to the shaft hole 16c _1, smoothly without bearing portion 16c and the support shaft 21 interferes Done in

Therefore, the capstan wheel 5
When the detection member 17 is pushed by the engagement protrusion 5a and further rotated in the counterclockwise direction (the direction of the arrow d) by the rotation of FIG.
As shown in FIG. 5, the first engagement piece 17b is
Is of the engagement flange portion 16b ₁ of the other half 16b side in a state of sliding contact engagement, detection lever 16 is rotated in the counterclockwise direction (arrow b direction), one half 16a side of the engaging protrusion 16a ₁ is moved on the protruding cam 15c of the rotating member 15 in the direction of the eccentric cam 15b.

Further, the rotation of the capstan wheel 5 causes the detection member 17 to rotate counterclockwise until the engagement projection 5a and the engagement edge 17d of the detection member 17 are disengaged, as shown in FIG. When rotated in the direction (direction of arrow d),
Detection lever 16 be further rotated in the counterclockwise direction (arrow b direction), the engaging projection 16a ₁ are moved position to the eccentric cam 15b side through the projecting cam 15c of the rotary member 15.

Until this state is reached, the rotation of the detecting member 17 in the counterclockwise direction (the direction of arrow d) causes the pressing arm 17e to push the lock plate 12 through the engagement end 12b. Push and slide to release the lock of the operation lever lock pin 13 by the engagement window 12a, and automatically release the lock of the operation lever. Each mode is stopped.

In this state, when the capstan wheel 5 is further rotated slightly, the engagement between the engagement protrusion 5a and the engagement edge 17d of the detection member 17 is released, and the detection member 17 is returned integrally. By the biasing force of the spring piece 17f, the spring piece is returned to the original position, that is, the position where it comes into contact with the rotation regulating projection 26.

The return rotation of the detection member 17 causes the first
Is separated from the rear surface of the end of the other half 16b of the detection lever 16, that is, the vertical interference engagement is released. As a result, the detection lever 16 is pushed back by the biasing force of the compression coil spring 23 so that the other half 16 b is separated from the rear surface of the mechanical chassis 1.
Other half side half portion of the shaft hole 16c ₁ of 6c is restored to the horizontal state in contact with the support shaft 21, engaging one half portion 16a side mating projections 16
a ₁ is opposed to the circumferential surface of the eccentric cam 15b of the rotary member 15 returns to the state or the stop time of tape running shown in FIG.

As described above, in the tape player of the present embodiment, the tape end detection and the shut-off operation are performed from the tape running to the end running state of the tape. After this operation, the detection lever 16 can be reliably returned to the position when the tape is running or stopped, and at the same time as the unlocking operation of each mode operation lever, so that there is no risk of malfunction occurring in the next operation. .

In the above embodiment, the case where the end of the tape is detected from the take-up reel base has been described. However, the present invention can be applied to a rotating body having a cam and a projection other than the reel base. Further, in the above-described embodiment, two detection members are used. However, the tape end detection device can be configured by using two or more detection members. Any one of the detection members is brought into interference engagement. In the above-described embodiment, each mode operation lever is automatically unlocked by detecting the tape end,
Although this is an example of stopping, it is naturally applicable to an automatic reversing device in an auto reverse tape player. Further, other than these, various changes can be made without departing from the spirit of the present invention.

[0046]

As described above, according to the present invention, in the tape end detecting device, the first detecting member which is displaced at the end of the tape is engaged with the other detecting member in the displaced state. It is possible to return to the tape running or stopped position reliably and at the same time, so that there is no risk of malfunction even if the next operation is performed by a quick and continuous operation, and the operation of the required mechanism accompanying the detection of the tape end is reliably performed. Thus, it is possible to provide a tape end detecting device of a tape drive device such as a tape drive such as an inexpensive tape player which can be improved in reliability, does not increase the number of components, is small, and does not cost components.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a surface side of a part of a transport in an example tape player to which the present invention is applied.

FIG. 2 is an exploded perspective view of the back side of a part of the transport.

FIG. 3 is a rear side plan view of an example of a tape end detecting device according to the present invention.

FIG. 4 is a longitudinal sectional view of a main part in FIG.

FIG. 5 is a rear side plan view showing an operation state of the tape end detection device according to the present invention.

FIG. 6 is a rear-side plan view showing a state where the detection lever is displaced from the state shown in FIG. 5;

7 is a rear side plan view showing an initial operation state in which the detection lever is returned from the state shown in FIG. 6;

8 is a longitudinal sectional view of a main part in FIG. 7;

9 is a rear side plan view showing an intermediate operation state in which the detection lever is returned from the state shown in FIG. 7;

10 is a rear side plan view showing a state where the detection lever is returned from the state shown in FIG. 9;

FIG. 11 is a rear side plan view of a conventional tape end detecting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mechanical chassis 2 Supply-side reel stand 3 Take-up-side reel stand 4 Capstan 5 Capstan wheel (rotation mechanism) 5a Engagement projection 9 Slip lever 11 Operation lever 12 Lock plate 14 Tape end detection / shutoff mechanism 15 Rotating member 15b Eccentric cam 15c Projecting cam 16 Detection lever (first detection member) 16a ₁ engagement projection 16b ₁ engagement projection 16b ₂ inclined guide surface 16b ₃ pressing projection 16d engagement piece 17 detection member (second detection member) 17b 1st engaging piece 17b ₁ inclined surface 17c 2nd engaging piece 17d engaging edge 17e pressing arm 17f return spring 23 compression coil spring

Claims (4)

(57) [Claims] A rotating member having a cam and a projection, a first detecting member for displacing from the cam side of the rotating member and engaging with the projection when the reel base stops due to the end of the tape, and detecting a tape end; In a tape end detection device of a tape drive device having another detection member displaced by being engaged with the first detection member displaced at the end and displaced by the drive mechanism, the other detection member includes An engagement portion that interferes with and engages with the first detection member is formed within a displacement movement range of the other detection member. After the tape end is detected, the other detection member is attached to the first detection member. And a tape, wherein the first engaging member is disengaged from the projection of the rotating member by interference engagement via the engaging portion, and is returned to a position at the time of running or stopping the tape. Drive tape De detection device. 2. The apparatus according to claim 1, wherein the first detecting member is rotationally displaced toward the fuselage in a direction parallel to an operating surface of the rotating member on which the cam and the projection are formed, and is oscillatingly displaced from the operating surface. 2. The tape end detecting device of a tape drive device according to claim 1, wherein the tape end detecting device is supported so as to be rotated. 3. The first detecting member is always supported in parallel with an operating surface of the rotating member on which the cam and the projection are formed, with an elastic supporting member interposed between the first detecting member and an airframe. 3. The tape end detecting device for a tape drive device according to claim 1, wherein 4. An engaging portion with which the other detecting member is engaged when the first detecting member is displaced by the driving mechanism, and the engaging portion is displaced by the other detecting member. 2. The tape end detecting device of a tape drive according to claim 1, wherein the first detecting member is returned to a position at the time of tape running or at the time of stopping via the member.