JP2000021049A - Tape tension adjusting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain the reduction of a load to a motor at the time of imparting the tension to a tape. SOLUTION: The mechanism is provided with a turning part 19 having an engaging chamfer 22 and a gear part 23 while being freely turnably supported with a chassis 6, a tension imparting part 21, a tension adjusting body 13 having a connection part 20 for connecting the turning part and the tension imparting part 21, a repulsive member 14 for pressing the tension adjusting body 13 to the direction where the tension is imparted by the tension imparting part 21, a driving gear 15b rotated integrally with the motor 15, a control gear 17 for transmitting the driving force of the motor to the turning part and also for controlling the tension adjusting body 13 to the position not in contact with the tape by being positioned in the engaging chamfer of the turning part when the transmission of the driving force of the motor to the turning part is finished, a connection arm 16 for connecting the motor and the control gear together in the rotatable state while being turned by the motor in the rotating direction, and a stopper 18 for stopping the connection arm 16 at the prescribed stop position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tape tension adjusting mechanism. More specifically, the present invention relates to a technique for reducing a load on a motor when tension is applied to a tape.

[0002]

2. Description of the Related Art For example, in a video tape recorder or the like, it is necessary that a tape be run with an appropriate tension.

FIG. 7 shows an example of a conventional tape tension adjusting mechanism.

A supply-side reel table b and a take-up reel table c are rotatably supported on the mechanical chassis a. The supply-side reel table b includes a supply-side reel engaging shaft d and a take-up reel table c. Is rotated integrally with the take-up reel engagement shaft e. A brake drum f is provided on the peripheral surface of the supply-side reel base b. The rotation of the reel bases b and c is performed by a reel base motor (not shown).

The tape tension adjusting mechanism g has a ten leg arm h and a brake band i.

A portion of the ten regi arm h near one end is rotatably supported by a mechanical chassis a, and a ten regi pin j is provided upright at the other end. The tensioning arm h is urged to rotate counterclockwise as viewed in FIG. 7 by a tension coil spring k stretched between one end of the tensioning arm h and a spring hook of the mechanical chassis a.

The brake band i has one end fixed to a fixed portion 1 provided on the mechanical chassis a and the other end connected to a position slightly closer to the other end than the rotation fulcrum of the ten leg arm h. I have. The intermediate portion of the brake band i is wound around the brake drum f of the supply-side reel base b.

When the tape cassette is mounted on the supply-side reel engagement shaft d and the take-up reel engagement shaft e, the tape m is pulled out of the cassette case by a tape pull-out mechanism (not shown), and is transferred to the mechanical chassis a. It is wound around the projecting guide posts n and o and other guide posts (not shown), a head drum, a capstan, and the like, and is passed through a predetermined tape path. Then, the portion of the tape m located between the guide posts n and o is resiliently contacted with the ten regi pin j erected on the ten regi arm h from the thickness direction of the tape m, whereby an appropriate tension is given to the tape m. When recording or reproducing the information signal on or from the tape m, the tape m runs while being held between the capstan and a pinch roller (not shown).

While the tape m is running, the tension on the tape m is changed due to, for example, uneven rotation of the capstan or a change in the frictional resistance between the tape m and the head drum.

When the tension on the tape m is increased, the tape m presses the tension pin j, and the tension arm h is rotated clockwise in FIG. 7, whereby the tightening force of the brake band i on the brake drum f is reduced. The load of the rotation of the supply-side reel base b and the supply-side reel engaging shaft d that rotates integrally with the supply-side reel base b is weakened, and the tension on the tape m is weakened.

When the tension on the tape m is weakened, the tension arm h is rotated counterclockwise in FIG. 7 by the spring force of the extension coil spring k.
As a result, the tightening force of the brake band i on the brake drum f is increased, the rotational load of the supply-side reel base b and the supply-side reel engaging shaft d rotating integrally therewith is increased, and the tension on the tape m is increased. .

In this way, the tension with respect to the tape m is adjusted so that it is always substantially constant.

[0013]

However, in the above-described tape tension adjusting mechanism g, when the tension for the tape m is adjusted, a load for rotation is always applied from the brake band i to the supply side reel base b. This load is a load generated by the spring force of the extension coil spring k and is relatively large.

Accordingly, a relatively large load for rotation is always applied to the reel base motor via the supply-side reel base b, and there is a problem that power consumption is correspondingly increased. . In particular, in the case of a portable so-called portable type device, the life of the battery is shortened, and it becomes necessary to use a large-capacity battery, so that the device becomes large or the weight of the device increases. Is disadvantageously increased.

Accordingly, it is an object of the present invention to provide a tape tension adjusting mechanism which overcomes the above-mentioned problems and reduces the load on a motor when tension is applied to a tape.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a tape tension adjusting mechanism according to the present invention comprises an engaging notch rotatably supported by a chassis and opened in a radial direction, and the engaging notch. A rotating portion having a gear portion formed on a surface that is continuous with the engagement notch on a peripheral surface of a portion that is not formed, a tension applying portion that contacts the tape, and a connection that connects the rotating portion and the tension applying portion. And a tension adjusting member having a portion, a resilient member for urging the tension applying portion to move the tension applying portion in a direction to contact the tape, a motor for running the tape, and a motor shaft of the motor. A drive gear that is coupled and rotated integrally with the motor; and a drive gear that is meshed with the drive gear and transmits the driving force of the motor to the rotation part of the tension adjustment body to rotate the rotation part and to rotate the rotation part with respect to the rotation part. A regulating gear which is positioned within the engagement notch of the rotating portion when the transmission of power is completed, engages with the rotating portion, and regulates the tension adjusting body to a non-contact position where the tension applying portion does not contact the tape; and a motor. A connection arm that has a predetermined frictional force with respect to the motor and is rotated in the rotation direction by the rotation of the motor and rotatably connects the motor and the restriction gear together with the restriction gear and the rotation unit A stopper is provided for stopping the connecting arm at a predetermined stop position when the state is released, and the motor is driven in one direction (forward rotation direction).
When the connecting arm is rotated in the forward direction, the engagement between the restricting gear located in the engaging notch of the tension adjusting body and the rotating portion is released, and the connecting arm is stopped by the stopper. And the tension adjusting member is rotated in the direction in which the tension applying portion and the tape come into contact with each other by the urging force of the resilient member, and the tension applying portion comes into contact with the tape to apply tension to the tape. When is rotated in the opposite direction (reverse direction) from one direction,
The connecting arm is rotated in the reverse direction so that the gear portion of the tension adjusting body meshes with the regulating gear, and the rotation of the regulating gear causes the tension adjusting body to contact the tension applying portion with the tape against the urging force of the resilient member. Is released in the direction in which the gear is released, and the rotation of the regulating gear causes the rotating portion to rotate by a predetermined angle, whereby the engagement between the regulating gear and the gear portion of the rotating portion is released, and the regulating gear further moves in the reverse direction. The control gear is rotated so that the regulating gear is positioned in the notch for engagement.

Therefore, in the tape tension adjusting mechanism of the present invention, a load generated based on the resilience of the resilient means is not applied to the motor for running the tape when the tension is applied to the tape.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the tape tension adjusting mechanism of the present invention will be described below with reference to the accompanying drawings.

In the embodiments described below, the tape tension adjusting mechanism of the present invention is applied to a tape tension adjusting mechanism in a small portable video camera.

The video camera 1 has a necessary member and mechanism arranged in an outer casing 2 and is a device dedicated to video recording. A finder 3 is provided at the upper end of the front surface of the outer casing 2, and a photographing lens 4 is disposed immediately below the finder 3 (see FIG. 1). A recording button 5 is provided on the front of the outer casing 2.
(See FIG. 1), and the recording mode and the stop mode for ending the recording are alternately set by operating the recording button 5.

A mechanical chassis 6 provided with predetermined mechanisms is disposed in a lower half portion of the outer casing 2 (FIGS. 1 and 2).
reference).

The mechanical chassis 6 has two reel bases 7,
7, rubber roller 8, head drum 9 and guide post 1
0, 10,... Are arranged (see FIG. 2). Then, when the tape cassette 11 is inserted from an insertion opening (not shown) formed in the outer casing 2 and is mounted on the reel bases 7, 7, the tape 11 a is pulled out of the cassette case of the tape cassette 11 by a tape drawing mechanism (not shown). ,
.., A rubber roller 8 and a capstan shaft, which will be described later, are passed through a predetermined tape path.

In a state where the tape 11a is pulled out of the cassette case by the pull-out mechanism, before the recording button 5 is operated, that is, in the stop mode, the tape 11a
And the tape 11a does not come into contact with the head of the head drum 9 (in FIG. 2, the state of the tape 11a to which the appropriate tension is not applied is indicated by a dashed line), and the recording button 5 is turned on. In the operated state, that is, in the recording mode, an appropriate tension is applied to the tape 11a by a tape tension adjusting mechanism to be described later.
1a is brought into contact with the head of the head drum 9 to enable recording (the state of the tape 11a to which an appropriate tension is applied is shown by a solid line in FIG. 2).

The tape tension adjusting mechanism 12 includes a tension adjusting body 13, a tension coil spring 14, a capstan motor 15, a connecting arm 16, a regulating gear 17, and a stopper 1.
8 (see FIG. 3).

The tension adjusting body 13 comprises a rotating part 19, a connecting part 20, and a roller part 21.

The turning portion 19 has a circular outer shape except for a portion in which a notch described later is formed, and is rotatably supported by the mechanical chassis 6. A notch 22 that opens downward as viewed in FIG. 3 is formed in the rotating portion 19, and the surface forming the notch 22 has a flat left end portion in FIG. Is formed as a first flat portion 22a extending from the outer periphery toward the rotation axis, and a portion continuous to the first flat portion 22a forms an arc shape and has a length of approximately one quarter of the circumference. 3 is formed as an arcuate surface portion 22b, and a portion on the right side as viewed in FIG. 3 that is continuous with the arcuate surface portion 22b is formed as a second flat portion 22c that extends in one direction. The notch 22 is formed such that the first flat portion 22a and the second flat portion 22c are substantially orthogonal.

The first flat portion 22 of the peripheral surface of the rotating portion 19
A gear portion 23 is formed at a portion opposite to the arc-shaped surface portion 22b with respect to the first flat portion 22a.
Further, a spring hook portion 24 is formed in a portion of the turning portion 19 on the right side of the turning fulcrum as viewed in FIG.

A connecting portion 20 protrudes from the peripheral surface of the rotating portion 19 substantially to the left as viewed in FIG. 3, and the connecting portion 20 is a clock of the gear portion 23 of the peripheral surface of the rotating portion 19. It protrudes from the part approaching the end on the rotation direction side.

A roller 21 is rotatably supported at the distal end of the connecting portion 20. The roller 21 is formed as a tension applying portion that comes into contact with the tape 11a and applies tension thereto.

One end of a tension coil spring 14 provided as a resilient member is attached to a spring hook portion 24 formed on the rotating portion 19, and the tension coil spring 14 is used to attach the tension adjusting member 13 to the tension adjusting body 13 as shown in FIG. The clockwise rotation is energized.

The mechanical chassis 6 is provided with a capstan motor 15 capable of rotating in both forward and reverse directions. The capstan shaft 15a of the capstan motor 15 is
Protrudes in the direction opposite to the side where is located. The capstan motor 15 is provided with a drive gear 15b which is coupled to the capstan shaft 15a and is rotated integrally therewith.

The connecting arm 16 is supported by the tip of the capstan shaft 15a. When the connecting arm 16 is supported by the capstan shaft 15a, a predetermined small frictional force is generated between the capstan shaft 15a and the connecting arm 16, and this frictional force is generated when the capstan shaft 15a is rotated. As a result, the connection arm 16 is rotated integrally with the capstan shaft 15a, and as described later, only the capstan shaft 15a is rotated when the rotation of the connection arm 16 is restricted by the stopper 18. Has become. The frictional force between the capstan shaft 15a and the connecting arm 16 is
It is sufficient that the force is sufficient to make the connecting arm 16 rotatable with this rotation when the is rotated, and is a small force.

The regulating gear 17 has a center shaft 17a and the center shaft 1a.
7a rotatably supported by the gear portion 17a.
The center shaft 17a protrudes from the gear portion 17b in a direction opposite to the side where the mechanical chassis 6 is located. The regulating gear 17 has a distal end portion of the center shaft 17a fixed to the other end portion of the connecting arm 16, and a gear portion 17b meshed with a driving gear 15b of the capstan motor 15. Also, the gear portion 17b
Is the same as the curvature of the arcuate surface portion 22b of the notch 22 formed in the rotating portion 19 of the tension adjusting body 13.

The stopper 18 is formed on the mechanical chassis 6, and the stopper 18 is connected integrally with the capstan motor 15 when the capstan motor 15 is rotated counterclockwise as viewed in FIG. This is for restricting the rotation of the arm 16. The stopper 18 is located substantially below the connecting arm 16 as viewed in FIG.
Is located corresponding to the movement path of the other end of the. The stopper 18 is formed at a position where the stopper 18 does not come into contact with the regulating gear 17 that is moved together with the connecting arm 16 when the connecting arm 16 is rotated.

The operation of the tape tension adjusting mechanism 12 will be described below (see FIGS. 3 to 6).

FIG. 3 shows a state in the stop mode. In this stop mode, as described above,
An appropriate tension is not applied to the tape 11a, and the tape 11a is not in contact with the head of the head drum 9.

In the stop mode, the regulating gear 1
7 is engaged with the arcuate surface portion 22b of the notch 22 so that the gear portion 17b is located in the notch 22. In the state where the gear portion 17b of the regulating gear 17 is engaged with the arcuate surface portion 22b of the notch 22 and is positioned inside the notch 22, the relative positional relationship between the rotating portion 19, the regulating gear 17, and the capstan motor 15 is set. As a result, when the rotating portion 19 attempts to rotate in the counterclockwise direction as viewed in FIG.
b presses the regulating gear 17 toward the center of the capstan motor 15, and a force F shown in FIG.
As a force F ′ is applied as a reaction to the rotation, the rotation of the rotating portion 19 is restricted by the regulating gear 17 and the
Unless the engagement state between 2b and the regulating gear 17 is released, it cannot be rotated in the counterclockwise direction.

Therefore, the rotation of the tension adjusting body 13 in the counterclockwise direction is regulated by the regulating gear 17, and is located at the pivot end in the clockwise direction (see FIG. 3).

When the recording button 5 is operated in the state shown in FIG. 3, the capstan motor 15 is rotated in the normal direction, that is, counterclockwise as viewed in FIG. 3, and the drive gear 15b is also rotated in the counterclockwise direction. Rotated. When the capstan motor 15 is rotated in the normal rotation direction, the above-described capstan shaft 15a
The connecting arm 16 is rotated in the counterclockwise direction by the frictional force between the control gear 17 and the gear portion 17b of the regulating gear 17 meshed with the driving gear 15b by the rotation of the driving gear 15b.
Is rotated clockwise.

The regulating gear 17 located in the notch 22 is moved substantially downward as viewed in FIG. 4 by the counterclockwise rotation of the connecting arm 16, whereby the gear portion of the regulating gear 17 is moved. The engagement state between 17b and the rotating portion 19 is released. At this time, since the gear portion 17b is rotated by the rotation of the drive gear 15b, the circular arc portion 22b of the notch 22 is formed.
And it moves while rolling on the 1st plane part 22a.

When the engagement between the regulating gear 17 and the rotating part 19 is released, the regulating gear 17 for the rotation of the rotating part 19 is released.
Is released, the tension adjusting body 13 is rotated counterclockwise by the resilient force of the tension coil spring 14, and the roller portion 21 is separated from the tape 11a to the right side as viewed in FIG. It is elastically contacted with the part located between the posts 10 and 10 (see FIG. 4). As described above, when the roller portion 21 is elastically contacted with the tape 11a, an appropriate tension is applied to the tape 11a, and
1a is brought into contact with the head drum 9, and the recording mode is set.

The rotating section 19 and the capstan motor 15
Is arranged so that the height position with respect to the mechanical chassis 6 is different from that of the mechanical chassis 6, so that even if the rotating portion 19 is rotated in the counterclockwise direction, it does not contact the capstan motor 15.

On the other hand, when the capstan motor 15 is further rotated in the counterclockwise direction, the connecting arm 16 is rotated in the counterclockwise direction until the other end of the connecting arm 16 contacts the stopper 18. . When the connecting arm 16 is in contact with the stopper 18 and rotation is restricted, the gear portion 17b of the restriction gear 17 is rotated clockwise because the drive gear 15b of the capstan motor 15 is rotated. .

When the connecting arm 16 is in contact with the stopper 18 and the rotation is restricted, the tension adjusting body 13 is rotated counterclockwise, and as shown in FIG. The gear portion 23 of 19 and the regulating gear 17 are vertically opposed as seen in FIG.

In the recording mode, the tape 11a is held between the capstan shaft 15a and a pinch roller (not shown), and travels in a predetermined direction by the rotation of the capstan shaft 15a to record an information signal on the tape 11a.

If the tension changes during the running of the tape 11a, the tape 11a is moved in the thickness direction. The tape 11a moves in accordance with the movement of the tape 11a in the thickness direction.
Is adjusted so that a substantially constant appropriate tension is applied to the.

When the recording button 5 is operated in the state shown in FIG. 4, the capstan motor 15 is rotated in the reverse direction, that is, clockwise as viewed in FIG. 4, and the drive gear 15b is also rotated clockwise. When the capstan motor 15 is rotated in the reverse direction, the connecting arm 16, whose movement has been restricted by the stopper 18, is rotated clockwise by the frictional force between the capstan motor 15 and the capstan shaft 15 a. By the rotation of the gear 15b, the regulating gear 17 meshed therewith is rotated in the counterclockwise direction.

When the recording button 5 is operated, the state in which the capstan shaft 15a and the pinch roller are sandwiched by the tape 11a is released, the rotation of the reel bases 7, 7 is stopped, and the running of the tape 11a is stopped. It is supposed to be.

The regulating gear 17 is rotated by the clockwise rotation of the connecting arm 16 while the gear portion 17b is rotating.
As a result, the gear portion 17b is meshed with the gear portion 23 of the rotating portion 19 located opposite to the gear portion 17b (see FIG. 5).

When the gear portion 17b is engaged with the gear portion 23, the rotating force of the capstan motor 15 is transmitted to the rotating portion 19 via the gear portion 17b, and the rotating portion 19 resiliently drives the extension coil spring 14. It is rotated clockwise as viewed in FIG. 5 against the force. Then, when the rotating portion 19 is rotated clockwise, the roller portion 21 is separated from the tape 11a, and the contact state between the roller portion 21 and the tape 11a is released (see FIG. 6). As a result, no tension is applied to the tape 11a by the tension adjuster 13, and the tape 11a does not come into contact with the head of the head drum 9.

When the rotating portion 19 is rotated to one end of the gear portion 23 to a position corresponding to the gear portion 17b of the regulating gear 17, the meshing state between the gear portion 17b and the gear portion 23 is released (FIG. 9). 6).

When the meshing state between the gear portion 17b and the gear portion 23 is released, the regulating gear 17 is moved substantially upward by the clockwise rotation of the connecting arm 16 as shown in FIG. 17b enters into the notch 22 of the rotating portion 19. At this time, the gear portion 17b of the regulating gear 17 is moved while rolling on the first flat portion 22a and the arcuate surface portion 22b of the notch 22, and the gear portion 17b is located in the notch 22 and a part of the gear portion 17b. 3 comes into contact with the arcuate surface portion 22b of the notch 22, and the stop mode is set.

When a part of the gear portion 17b abuts on the arcuate surface portion 22b of the notch 22 and the gear portion 17b is located in the notch 22, the position of the tension adjusting body 13 or the regulating gear 17 is detected by a detecting means (not shown). The capstan motor 15 is detected, and a command signal to stop the capstan motor 15 is issued based on the detection result, and the capstan motor 15 is stopped.

As described above, in the tape tension adjusting mechanism 12, the load on the capstan motor 15 rotates the gear portion 17b of the regulating gear 17 when the tape 11a is properly tensioned. Since only a small frictional force and a small frictional force between the capstan shaft 15a and the connecting arm 16 are applied, the load on the capstan motor 15 is very small.

Accordingly, power consumption can be reduced accordingly, and the size and capacity of a power supply, for example, a battery, can be reduced, and the video camera 1 can be reduced in size and weight. .

When the engagement between the regulating gear 17 and the rotating portion 19 is released, the gear portion 17b of the regulating gear 17 is disengaged.
Is rolled on the arcuate surface portion 22b of the notch 22 and the first flat portion 22a, so that when the engagement between the gear portion 17b and the rotating portion 19 is released, the regulating gear 17 and the arcuate surface portion 22b
As compared with the case where the first flat portion 22a is in sliding contact with the first flat portion 22a, the load on the capstan motor 15 can be reduced, and the power consumption can be further reduced.

It should be noted that the specific shapes and structures of the respective parts shown in the above-described embodiment are merely examples of the embodiment when practicing the present invention.
These should not be construed as limiting the technical scope of the present invention.

[0058]

As is apparent from the above description, the tape tension adjusting mechanism of the present invention is a tape tension adjusting mechanism for adjusting the tension of the tape drawn from the tape cassette, and is rotatably mounted on the chassis. A rotating portion having an engaging notch that is supported and opened in the radial direction, and a gear portion formed on a surface that is continuous with the engaging notch on a peripheral surface of a portion where the engaging notch is not formed; A tension applying portion that applies tension by contact, a tension adjusting body that has a connecting portion that connects the rotating portion and the tension applying portion, and a moving force in a direction in which the tension applying portion contacts the tape on the tension adjusting body. A resilient member for urging, a motor for running the tape, a drive gear coupled to a motor shaft of the motor and integrally rotated with the motor, and a drive gear The driving force of the motor is transmitted to the rotating portion of the tension adjusting member to rotate the rotating portion, and when the transmission of the driving force of the motor to the rotating portion is completed, the engagement portion of the rotating portion is engaged. A regulating gear which engages with the rotating part and regulates the tension adjusting body to a non-contact position where the tension applying part does not contact the tape, and has a predetermined frictional force with respect to the motor and is rotated by the rotation of the motor. The connecting arm is pivoted in the direction and connects the motor and the regulating gear in a rotatable state, and the connecting arm is stopped at a predetermined stop position when the engaging state between the regulating gear and the rotating portion is released. When the motor is rotated in one direction (forward direction), the connecting arm is rotated in the forward direction to rotate with the regulating gear located in the engagement notch of the tension adjusting body. Disengagement with moving part The connecting arm is stopped at the stop position by the stopper, and the biasing force of the resilient member causes the tension adjusting member to rotate in the direction in which the tension applying portion and the tape come into contact, so that the tension applying portion comes into contact with the tape and the tape When the motor is rotated in the opposite direction (reverse direction) to one direction, the connecting arm is rotated in the reverse direction, and the gear portion of the tension adjusting body meshes with the restriction gear, and the restriction gear The rotation causes the tension adjusting body to rotate against the urging force of the resilient member in a direction in which the contact between the tension applying portion and the tape is released, and the rotation of the regulating gear causes the rotation portion to rotate by a predetermined angle. Then, the engagement between the regulating gear and the gear portion of the rotating portion is released, and the regulating gear is further rotated in the reverse direction so that the regulating gear is located in the engagement notch. You.

Therefore, when tension is applied to the tape, the load on the motor is very small, so that the power consumption can be reduced accordingly, and the size and capacity of the power supply, for example, the battery, can be reduced. Thus, the size and weight of the device using the tape tension adjusting mechanism can be reduced.

According to the second aspect of the present invention, when the connecting arm is rotated in the normal rotation direction and the engagement state between the regulating gear and the rotating portion is released, the regulating gear is engaged with the engaging notch. Since the rolling is performed on the surface to be formed, when the engagement state between the regulating gear and the rotating portion is released, the regulating gear and the surface forming the engagement notch are slidably contacted. Compared to the case,
The load on the motor can be reduced, and the power consumption can be further reduced.

[Brief description of the drawings]

FIG. 1 shows an embodiment in which the tape tension adjusting mechanism of the present invention is applied to a tape tension adjusting mechanism in a small portable video camera together with FIGS. 2 to 6, and FIG. 1 is a schematic perspective view of the video camera. It is.

FIG. 2 is a schematic diagram illustrating a state of a tape to which an appropriate tension is applied and a state of a tape to which an appropriate tension is not applied.

FIG. 3 is a diagram for explaining the operation of the tape tension adjusting mechanism together with FIGS. 4 to 6, and FIG. 3 is a schematic enlarged plan view of the tape tension adjusting mechanism showing a state of a stop mode.

FIG. 4 is a schematic enlarged plan view of the tape tension adjusting mechanism showing a state in which the engagement state between the regulating gear and the rotating unit is released and tension is applied to the tape, following FIG.

FIG. 5 is a schematic enlarged plan view of the tape tension adjusting mechanism showing a state in which the capstan motor is rotated in the reverse direction and the regulating gear and the gear portion of the rotating portion are engaged.

FIG. 6 is a schematic enlarged plan view of the tape tension adjusting mechanism showing a state in which the meshing state between the regulating gear and the gear section of the rotating section is released, following FIG. 5;

FIG. 7 is a schematic plan view of a main part showing an example of a conventional tape tension adjusting mechanism.

[Explanation of symbols]

6 mechanical chassis (chassis), 11a tape, 12
... Tape tension adjusting mechanism, 13 ... Tension adjusting body, 14 ... Tension coil spring (elastic member), 15 ... Capstan motor (motor), 15a ... Capstan shaft (motor shaft), 15b ... Drive gear, 16 ... Connection arm , 17
... Regulator gear, 18 ... Stopper, 19 ... Rotating part, 20 ... Connecting part, 21 ... Roller part (tension applying part), 22 ... Notch (notch for engagement), 23 ... Gear part

Claims (2)

[Claims] 1. A tape tension adjusting mechanism for adjusting the tension of a tape pulled out of a tape cassette, comprising: a notch for engagement rotatably supported by a chassis and opened in a radial direction; A rotating portion having a gear portion formed on a surface which is continuous with the engagement notch on a peripheral surface of a portion which is not formed, a tension applying portion for applying tension by contacting the tape, a rotating portion and a tension applying portion A tension adjusting member having a connecting portion for connecting the tension adjusting member, a resilient member for urging the tension adjusting portion to move in a direction in which the tension applying portion contacts the tape, a motor for running the tape, and the motor A drive gear that is coupled to the motor shaft of the motor and is rotated integrally with the motor; and a drive gear that is meshed with the drive gear and transmits the driving force of the motor to the rotating portion of the tension adjusting body to rotate the rotating portion. When the transmission of the driving force of the motor to the rotating portion is completed, the tension adjusting member is positioned in the engaging notch of the rotating portion and engages with the rotating portion so that the tension applying portion does not contact the tape. A regulating gear for regulating the position, a coupling arm having a predetermined frictional force with respect to the motor, being rotated in the rotational direction by rotation of the motor, and coupling the motor and the regulating gear so as to be rotatable together; A stopper for stopping the connection arm at a predetermined stop position when the engagement state between the gear and the rotating portion is released, and the connection arm moves in one direction when the motor is rotated in one direction. The engagement between the regulating gear, which has been rotated and located in the engagement notch of the tension adjusting body, and the rotating portion is released, the connecting arm is stopped at the stop position by the stopper, and the urging force of the elastic member is reduced. As a result, the tension adjusting body is rotated in a direction in which the tension applying section and the tape come into contact, and the tension applying section comes into contact with the tape to apply tension to the tape, and the motor rotates in the other direction opposite to one direction. When done
When the connecting arm is rotated in the other direction, the gear portion of the tension adjusting member and the regulating gear mesh with each other, and the rotation of the regulating gear causes the tension adjusting member to move between the tension applying portion and the tape against the urging force of the resilient member. In addition to the rotation in the direction in which the contact is released, the rotation of the restriction gear rotates the rotation part by a predetermined angle, and the engagement between the restriction gear and the gear part of the rotation part is released, and the restriction gear is further rotated. The regulating mechanism is rotated in the direction to position the regulating gear in the notch for engagement. 2. When the connecting arm is rotated in one direction and the engaging state between the regulating gear and the rotating portion is released, the regulating gear is rolled on a surface forming the engaging notch. The tape tension adjusting mechanism according to claim 1, wherein