JPH0430657B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a tape end detection device for a magnetic recording/reproducing device using a planetary gear system.

Conventional configurations and their problems In recent years, there have been remarkable advances in technology for making magnetic recording and reproducing devices smaller, thinner, and more multifunctional. something is wanted.

A conventional tape end detection device for a magnetic recording/reproducing device will be described below.

FIG. 1 is a plan view of essential parts of a conventional example in a stopped state, and FIG. 2 is a sectional view taken along the line A-A in FIG. 1. In FIG. 1, 1 is a flywheel driven by a motor (not shown) and rotates at a constant speed, 2 is a flywheel gear provided integrally with the flywheel, and 3 is a capstan implanted in the flywheel 1. . Reference numeral 4 denotes an intermediate gear rotatably provided on a shaft 30 implanted in the substrate, and a gear 4a is provided on the outer periphery of the central shaft portion, and a gear 4b that meshes with the flywheel gear 2 is also provided on the outer periphery. It is being

Reference numeral 5 designates a reel stand having a gear 6 integrally provided at its lower part, and is rotatably provided on a shaft 8 implanted in a base plate 7. A reel gear 9 meshes with the gear 4b of the intermediate gear 4 and is pressed against the upper surface of the gear 6 of the reel stand 5 by a compression spring 11 via a friction member 10. 12 is the shaft 1 implanted in the substrate 7
This is a relay gear that is rotatably provided on the intermediate gear 3 and meshes with the gear 4a of the intermediate gear 4.

Reference numeral 14 denotes a sun gear rotatably provided on a shaft 15 implanted in the substrate 7, and a gear 14a is provided on the outer periphery of the central shaft portion, and a gear 14 is also provided on the outer periphery.
b, and the gear 14b meshes with the relay gear 12. 16 is a planetary wheel that meshes with the gear 14a. A control wheel 17 is rotatably provided on the shaft 15, meshes with the reel stand 6, and integrally includes the rotating shaft 17a of the planetary wheel 16. 18 is an internal tooth 18 that meshes with the planetary wheel 16.
This is a detection wheel having a cam surface 18b near the outer periphery. Reference numeral 19 denotes an operating rod which is slidably guided by shafts 20 and 21 implanted in the base plate 7, and biased by a spring 22. 23 is an operation button fixed to the operation rod 19. Reference numeral 24 denotes a locking member, which is rotatably provided around a shaft 25 embedded in the base plate 7, and is a locking pin 2 that locks the operating rod 19.
6 is installed and is biased by a spring 27. 2
A detection arm 8 is rotatably mounted on a shaft 29 implanted in the locking member 24, and has a claw 28a that traces the cam surface 18b of the detection wheel 18. The spring 27 is formed so that it escapes from the cam surface 18b when rotating in the opposite direction, and bites into it when rotating counterclockwise.
The cam surface 18a is pressed against the cam surface 18a.

The operation of the conventional tape end detection device for a magnetic recording/reproducing apparatus constructed as described above will be described below.

First, when the operating button 23 is pressed, the operating rod 19 moves to the left against the biasing force of the spring 22, and is locked by a lock pin 26 implanted in the lock member 24. When the flywheel 1 is driven by a motor (not shown) and rotates at a constant speed counterclockwise, the flywheel gear 2 integrally formed with the flywheel 1 rotates.
The intermediate gear 4 that meshes with rotates clockwise at a constant speed. Also, a gear 4a on the outer periphery of the central axis of the intermediate gear 4
The relay gear 12 meshing with the relay gear 12 rotates at a constant speed counterclockwise, and the sun wheel 14 meshing with the relay gear 12 rotates at a constant speed clockwise. Further, the reel gear 9 meshes with the intermediate gear 4 and rotates at a constant speed in the counterclockwise direction, and is biased by the compression spring 5 and the friction member 1
0 to the reel stand 5, and the reel stand 5 winds the tape.

The control wheel 17 is driven clockwise by a gear 6 integrally formed on the reel stand 5, and the sun wheel 14
When the rotation of the tape is transmitted to the detection wheel 18 via the planet wheel 16, the detection wheel 18 is also set to rotate clockwise while the tape is running. At this time, the claw 28a of the detection arm 28 traces the cam surface 18b of the detection wheel 18, but when the detection wheel 18 is rotating clockwise, the claw 28a continues to swing while tracing the cam surface 18b. .

At the end of the tape, the reel stand 5 stops rotating, and the control wheel 17 also stops rotating. At this time, since the rotation axis 17a of the planetary wheel 16 is stationary, the planetary wheel 16 rotates counterclockwise in response to the rotation of the gear 14a of the sun wheel 14, which is rotating at a constant speed clockwise, and the detection wheel 18 is rotated counterclockwise. Drive counterclockwise. At this time, when the protrusion of the cam surface 18b of the detection wheel 18 hits the claw 28a of the detection arm 28, the claw 28a bites into the protrusion.
The driving force of the detection wheel 18 pushes the detection arm 28 in the direction B, rotates the locking member 24 counterclockwise,
Operating rod 1 locked by a lock pin
9 and release it.

However, in the above configuration, a planetary gear device is added for end detection in addition to the rotation transmission path to the reel stand mechanism.
It has problems in that it requires a large number of parts and is difficult to miniaturize.

Purpose of the invention The present invention solves the above-mentioned conventional problems.
It is an object of the present invention to provide a tape end detection device for a magnetic recording/reproducing device that is small in size, has a small number of component parts, and is easy to assemble with a small number of assembly steps.

Structure of the Invention The present invention includes a reel stand that is formed integrally with a reel hook that drives a tape, has means for transmitting rotational drive, and is rotatably provided on a substrate, and a reel that is pressed into contact with the reel stand via a friction member. a reel stand mechanism having a wheel; a sun wheel that receives rotational drive from a constant speed rotating body and transmits it to the reel wheel; a control wheel that receives rotational drive from the reel stand and has the same rotation center as the sun wheel; A planetary wheel that meshes with an external gear formed integrally with the sun wheel and is rotatably provided on a pin implanted in the control wheel, an internal gear that meshes with the planetary wheel, and a cam surface provided near the outer periphery. The sun wheel and the detection wheel rotate in the same direction while the tape is running, and when the tape ends, the sun wheel and the detection wheel rotate in the same direction. Then, the detection means detects the end of the tape by utilizing the fact that the detection wheel rotates in the opposite direction to the sun wheel, and the planetary gear device transmits rotational drive from the constant speed rotating body to the reel table mechanism. This is a tape end detection device that is characterized by being configured as follows. As mentioned above, the planetary gear device itself transmits the rotational drive from the constant speed rotating body to the reel stand mechanism, so it can be significantly downsized and has a reduced number of component parts. Therefore, the number of assembly steps is also reduced, and assembly can be facilitated.

DESCRIPTION OF EMBODIMENTS FIG. 3 is a plan view of essential parts of an embodiment of the present invention showing a stopped state, and FIG. 4 is a cross-sectional view taken along the line C--C in FIG. 3. In FIG. 3, 101 is a flywheel driven by a motor (not shown) and rotates at a constant speed, 102 is a flywheel gear integrally provided with the flywheel, and 103 is a capstan implanted in the flywheel 101. be.

104 is a sun wheel rotatably provided on a shaft 105 implanted in the substrate, and a gear 104a is provided on the outer periphery of the central shaft portion, and a gear 104a is also provided on the outer periphery.
04b is provided, and the gear 104b meshes with the flywheel gear 102. 106 is a planet wheel that meshes with the gear 104a. 10
Reference numeral 7 denotes a control wheel which is rotatably provided on the shaft 105 and integrally includes the rotating shaft 107a of the planetary wheel 106. Reference numeral 108 denotes a detection wheel having internal teeth 108a that mesh with the planetary wheel 106 and a cam surface 108b near the outer periphery. 109 is the control car 10 at the bottom.
This is a take-up reel stand integrally provided with a gear 110 that meshes with the gear 7, and is rotatably provided on a shaft 112 implanted in a base plate 111. A reel gear 113 meshes with the gear 104b of the sun wheel 104 and rotates at a constant speed, and is pressed against the upper surface of the gear 110 of the reel stand 109 by a compression spring 115 via a friction member 114.

Reference numeral 116 denotes an operating rod, which is slidably guided by shafts 117 and 118 implanted in the base plate 111, and is biased by a spring 119. 120 is an operation button fixed to the operation rod. 121 is a locking member and the board 11
The operating rod 116 is provided with a lock pin 123 for locking the operating rod 116, and is biased by a spring 124. Reference numeral 125 denotes a detection arm, which is rotatably mounted on a shaft 126 implanted in the locking member 121, and is attached to the cam surface 10 of the detection wheel 108.
The claw 125a has a claw 125a that traces the claw 8b.
5a is formed so that it escapes from the cam surface 108b when the detection wheel 108 rotates clockwise, and bites into it when the detection wheel 108 rotates counterclockwise.
7 to press against the cam surface 108b.

The operation of the tape end detection mechanism of the magnetic recording/reproducing apparatus of this embodiment configured as described above will be explained below.

FIG. 5 is an explanatory diagram of running the tape at constant speed during playback, recording, etc. First, when the operation button 120 is pressed, the operation rod 116 moves to the left against the biasing force of the spring 119 and is locked by a lock pin 123 embedded in a lock member 121. When the flywheel 101 is driven by a motor (not shown) and rotates counterclockwise at a constant speed, the flywheel 101
A sun wheel 104 meshing with a flywheel gear 102 integrally formed with the main body rotates at a constant speed clockwise.
The reel gear 113 meshes with the sun wheel 104 and rotates at a constant speed counterclockwise, is biased by a compression spring 115 and drives the reel stand 109 via the friction member 114, so that the reel stand 109 rolls the tape. Wind it up.

The control wheel 107 meshes with a gear 110 formed integrally with the reel stand 109 and is driven clockwise.
The detection wheel 108 is also set to rotate clockwise while the tape is running so that the rotation of the sun wheel 104 is transmitted to the detection wheel 108 via the planet wheel 106. At this time, the claw 125a of the detection arm 125 traces the cam surface 108b of the detection wheel 108, but when the detection wheel 108 is rotating clockwise, the claw 125a continues to swing while tracing the cam surface 108b. . Reel stand 109 at the end of the tape
The rotation of the control wheel 107 is stopped, and the rotation of the control wheel 107 is also stopped. At this time, since the rotation axis 107a of the planetary wheel 106 is stationary, the planetary wheel 106 rotates counterclockwise in response to the rotation of the gear 104a of the sun wheel 104, which is rotating at a constant speed clockwise, and the detection wheel 108 is rotated counterclockwise. Drive counterclockwise. At this time, the cam surface 1 of the detection wheel 108
When the projection 08b hits the claw 125a of the detection arm 125, the claw 125a bites into the projection of the cam surface 108b, and the driving force of the detection wheel 108 is transferred to the detection arm 12.
5 in the D direction, and lock the locking member 121 with the spring 12.
4 in the counterclockwise direction to disengage the lock pin 123 that locks the operating rod 116, thereby releasing the operating rod 116 and stopping the tape.

As described above, according to this embodiment, the planetary gear device itself transmits the rotational drive from the constant speed rotating body to the reel stand mechanism, so it can be significantly miniaturized, the number of component parts is small, and the number of assembly steps is also reduced. Assembly is easy.

Effects of the Invention The present invention comprises a reel stand which is formed integrally with a reel hook for driving a tape and has means for transmitting rotational drive and is rotatably provided on a substrate, and a reel which is pressed into contact with the reel stand via a friction member. a reel stand mechanism having a wheel; a sun wheel that receives rotational drive from a constant speed rotating body and transmits it to the reel wheel; a control wheel that receives rotational drive from the reel stand and has the same rotation center as the sun wheel; A planetary wheel meshing with an external gear formed integrally with the sun wheel and rotatably provided on a pin implanted in the control wheel, an internal gear meshing with the planetary wheel, and a cam surface provided near the outer periphery. It is equipped with a planetary gear mechanism having a detection wheel, and a means for tracing the cam surface of the detection wheel to detect the rotating direction of the detection wheel.While the tape is running, the sun wheel and the detection wheel rotate in the same direction, and at the end of the tape, The detecting means detects the end of the tape by utilizing the fact that the detecting wheel rotates in the opposite direction to the sun wheel, and the planetary gear device transmits rotational drive from the constant speed rotating body to the reel stand mechanism. By configuring
It is possible to realize an excellent tape end detection device that can be significantly miniaturized, has a small number of component parts, and can be easily assembled with fewer man-hours.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the main parts of a tape end detection device of a conventional magnetic recording/reproducing device, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a tape end in an embodiment of the present invention. Plan view showing main parts of the detection device, No. 4
The figure is a sectional view taken along the line CC in FIG. 3, and FIG. 5 is a plan view showing the tape running at a constant speed during playback or recording. 101... Flywheel, 104... Sun wheel,
106... Planetary car, 107... Control car, 108...
... detection wheel, 109 ... reel stand, 113 ... reel gear, 116 ... operation rod, 120 ... operation button, 121 ... lock member, 125 ... detection arm.

Claims (1)

[Claims] 1. A reel stand that is formed integrally with a reel hook that drives the tape, has a means for transmitting rotational drive, and is rotatably provided on a substrate, and a reel wheel that is pressed into contact with the reel stand via a friction member. a sun wheel that receives the rotational drive of the constant speed rotating body and transmits it to the reel wheel, a control wheel that receives rotational drive from the reel stand and has the same rotation center as the sun wheel, and is integrated with the sun wheel. a planetary wheel that meshes with an external gear formed on the rim and is rotatably provided on a pin implanted in the control wheel; an internal gear that meshes with the planetary wheel; and a detection wheel that has a cam surface near its outer periphery. and a means for detecting the rotational direction of the detection wheel by tracing the cam surface of the detection wheel, and when the control wheel is rotating in the same direction as the sun wheel, the detection wheel is rotated in the same direction as the sun wheel. The detection wheel rotates in the same direction and when the control wheel stops, the detection wheel rotates in the opposite direction to the sun wheel, and the detection wheel rotates in the opposite direction at the end of the tape using the above detection means to detect the end of the tape. What is claimed is: 1. A tape end detection device, characterized in that the planetary gear device is configured to transmit rotational drive from the constant speed rotating body to the reel stand mechanism.