JPS60164940A - Tape end detector - Google Patents

Abstract

PURPOSE:To attain ease of assembling by allowing a planetary gear device itself to deliver rotating drive from a constant speed turning body to a reel stand mechanism to attain remarkably miniaturization and to decrease the number of components. CONSTITUTION:A control wheel 107 meshes with a gear 110 formed incorporatedly with a reel stand 109 and is driven counter clockwise. In order to deliver the rotation of a sun wheel 104 to a detecting wheel 108 via a planetary wheel 106, the detecting wheel 108 is set to be turned clockwise during tape running. In this case, a claw 125a of a detection arm 125 traces a cam face 108b of the detection wheel 108, and when the detection wheel 108 is turned clockwise, the claw 125a keeps shaking while tracing the cam face 108b. The turning of the reel stand 109 is stopped at the tape and and the turning of the control wheel 107 is stopped also. Since the position of a turning shaft 107a of the planetary wheel 106 is stopped in this case, the wheel is rotated counter clockwise by the roation of the gear 104a of the sun wheel 104 to drive the detection wheel 108 counter clockwise.

Description

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

Conventional configurations and their problems In recent years, there have been remarkable advances in the technology of making magnetic recording and reproducing devices smaller, thinner, and more multifunctional. being criticized.

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

FIG. 1 is a plan view of the main parts of the conventional example in a stopped state;
FIG. 2 is a sectional view taken along the line AA 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 on the body of the flywheel, and 3 is a capstan implanted in the flywheel 1. It is. 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

5 is a take-up reel stand with a gear 6 integrally provided at the bottom;
It is rotatably provided on a shaft 8 implanted in the substrate 7.

9 is a friction member 1 that meshes with gear 4b of intermediate gear 4;
This is a reel gear that is biased against the upper surface of the gear 6 of the reel stand 6 by a compression spring 11 via the reel gear 6. Reference numeral 12 denotes an intermediate gear which is rotatably provided on a shaft 13 implanted in the substrate and meshes with the gear 4a of the intermediate gear 4.

14 is a sun gear rotatably provided on a shaft 16 implanted in the substrate 7, and a gear 14a is provided on the outer periphery of the central shaft portion, and a gear 14b is also provided on the outer periphery.
The gear 14b meshes with the relay gear 12. 16 is a planetary wheel that meshes with the gear 14a. 1T is a control wheel which is rotatably provided on the shaft 16, meshes with the reel stand 6, and integrally includes the rotating shaft 17a of the planetary wheel 16.

Reference numeral 18 denotes a detection wheel having internal teeth 18a that mesh with the planetary wheel 16 and a cam surface 18b near the outer periphery.

Reference numeral 19 denotes an operating rod, which is guided by a shaft 2o and a shaft 21 implanted in the base plate 7, and is slidably provided 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 26 implanted in the base plate, and has a opening for locking the operating rod 19;
6 is installed and is biased by spring 2. 28 is a detection arm; a shaft 29 implanted in the locking member 24;
The cam surface 18b of the detection wheel 18
It has a claw 28a that traces the detection wheel 18, and the claw is formed so that it escapes from the cam surface 18b when the detection wheel 18 rotates clockwise, and bites into it when it rotates counterclockwise.
A spring 27 presses 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 you press the operation button 23, the operation port/socket 19 will spring 2.
It moves to the left against the biasing force of 2, and is locked by a cup pin 26, which is a port 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 intermediate gear 4 meshing with the flywheel gear 2 formed integrally with the flywheel 1 rotates at a constant speed clockwise.

Further, the relay gear 12 meshing with the gear 4a on the outer periphery of the central shaft portion of the intermediate gear 4 rotates at a constant speed in the counterclockwise direction.
The sun wheel 14 meshing with the sun wheel 2 rotates clockwise at a constant speed. Further, the reel gear 9 meshes with the intermediate gear 4 and rotates at a constant speed counterclockwise, and is urged by the compression spring 5 and transmits rotation to the reel stand 6 via the friction member 1o, so that the reel stand 6 Winding the tape.

The control wheel 17 is driven clockwise by a gear 6 integrally formed on the reel stand 6, and when the rotation of the sun wheel 14 is transmitted to the detection wheel 18 via the planetary wheel 16, the detection wheel 18 is driven while the tape is running. is also set to rotate clockwise.

- 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 swings while tracing the cam surface 18b. continue.

At the end of the tape, the reel stand 5 stops rotating, and the control wheel 170 also stops rotating. At this time, since the rotation axis 17a of the planet wheel 16 is stationary, the planet 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, the protrusion on the cam surface 18b of the detection wheel 18 touches the detection arm 2.
When it hits the claw 28a of No. 8, the claw 28a bites into the protrusion, and the driving force of the detection wheel 18 pushes the detection arm 28 in the direction B, causing the lock portion side 24 to rotate counterclockwise, and is locked by the lock pin. The operation rod 19 is disengaged and released.

However, in the above configuration, in addition to the rotation transmission path to the reel stand mechanism, a planetary gear device is added for end detection, so there are many parts and it is difficult to downsize. There was a problem.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and an object thereof is 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 therefore requires few assembly steps and is easy to assemble. do.

Structure of the Invention The present invention comprises a reel stand that is formed integrally with a reel hook that drives the tape and has means for transmitting rotational drive and is rotatably provided on a substrate, and a reel stand that is press-contacted to the reel stand via a 7-reaction member. a sun wheel that receives rotational drive from a constant speed rotating body and transmits it to the reel wheel; and 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 near the outer periphery. The sun wheel and the detection wheel rotate in the same direction while the tape is running. 7. At the end of the tape, the detecting 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 rotates the reel table mechanism from the constant speed rotating body. This tape end detection device is characterized in that it is configured to transmit rotational power, and as described above, the planetary gear device itself transmits the rotational drive from the constant speed rotating body to the reel table mechanism, so that it can be significantly miniaturized. The number of component parts is small, and therefore the number of man-hours required for assembly is also small, making assembly easy.

DESCRIPTION OF THE 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 sectional view taken along the line C--C in FIG. 3. In FIG. 3, 101 is a flywheel that is driven by a motor (not shown) and rotates at a constant speed, 102 is a flywheel gear provided integrally with the flywheel, and 103 is a flywheel implanted in the flywheel 101. It's a capstan.

Reference numeral 104 denotes a sun wheel rotatably mounted on a shaft 105 implanted in the substrate.A gear 104a is provided on the outer periphery of the central shaft portion of the sun wheel, and a gear 104b is also provided on the outer periphery of the sun wheel. meshes with the flywheel gear 102. 106 is a planetary wheel that meshes with the gear 10'4a.

A control wheel 107 is rotatably provided on the shaft 105 and integrally includes a 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 circumference. 1
Reference numeral 09 denotes a take-up reel stand integrally provided with a gear 110 meshing with the control wheel 107 at its lower part, and is rotatably provided on a shaft 112 implanted in a base plate 111. 113 rotates at a constant speed in combination with the gear 1o4bK of the sun wheel 104,
The reel gear is pressed against the upper surface of the gear 110 of the reel base 109 by a compression spring 115 via a friction member 114.

Reference numeral 116 denotes an operating rod, which is implanted in the substrate 111 and is connected to r+c.
The shaft is slidably guided by an r-shaft 118 and biased by a spring 119.

Reference numeral 120 denotes an operation button fixed to the operation port. Reference numeral 121 denotes a locking member, which is rotatably provided around a shaft 122 implanted in the base plate 111, and has a locking pin 123 implanted therein which engages the operating rod 116, and is biased by a spring 124. has been done. Reference numeral 125 denotes a detection arm, which is connected to the shaft 12 implanted in the above-mentioned port 121.
6 is rotatably provided on the cam surface 1 of the detection wheel 108.
The claw 125a has a claw 126a that traces 08b.
When the detection wheel 108 rotates clockwise, the cam surface 10
The cam surface 108b is formed to bite into the spring 127 when it escapes from the sun and rotates counterclockwise.
It is pressed and biased.

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. 6 is a detailed explanatory diagram of constant speed tape running 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 implanted in the lock part lug 121. When the flywheel 101 is driven by a motor (not shown) and rotates at a constant speed counterclockwise, the sun wheel 104 meshing with a flywheel gear 1o2 formed integrally with the flywheel 101 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 hook john member 114, so that the reel stand 109 winds the tape. take.

The control wheel 107 meshes with a gear 110 formed integrally with the reel stand 109 and is driven clockwise, and the sun wheel 1040
The detection wheel 10B is also set to rotate in the open direction while the tape is running so that the rotation is transmitted to the detection wheel 108 via the planetary wheel 106. At this time, the cam surface 1 of the detection wheel 108
o8b is traced by the pawl 126a of the detection arm 125, and when the detection wheel 108 is rotating clockwise, the pawl 125a continues to swing while tracing the cam surface 1o8b. At the end of the tape, the reel stand 109 stops rotating, and the control wheel 1070 also stops rotating. At this time, the planetary wheel 106
Since its rotating shaft 10a is stationary, it 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 moves the detection wheel 108 counterclockwise. Drive to. At this time, the cam surface 10 of the detection wheel 108
When the projection 8b hits the claw 125a of the detection arm 125, the claw 125aiIi bites into the projection of the cam surface 108b,
The driving force of the detection wheel 108 pushes the detection arm 125 in the D direction, rotates the lock member 121 in the counter-opening direction against the urging force of the spring 124, and locks the lock pin 123 that locks the operating loft 116. is released and the operating rod 116 is released to stop 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 and the number of component parts is small, so the number of assembly steps is also reduced. can be done easily.

Effects of the Invention The present invention includes a reel stand that is formed integrally with a reel hook that drives the tape, has means for transmitting rotational drive, and is rotatably provided on a substrate, and is pressed into contact with the reel stand via a friction member. a reel stand mechanism having a reel 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 near the outer periphery. The sun wheel and the detection wheel rotate in the same direction while the tape is running, and the tape is rotated in the same direction. At the end, the detecting 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 stand mechanism. With this configuration, 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 a small number of assembly steps.

[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 line A-A in FIG.
FIG. 3 is a plan view showing the main parts of a tape end detection device according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view of FIG.
FIG. 5 is a plan view showing a state in which the tape is running at a constant speed during playback or recording. 101... Flywheel, 104...
Sun wheel, 106... Planet wheel, IQ7...
Control vehicle, 108...Detection vehicle, 109...
・Reel stand, 113...Reel gear, 116・
...Operation rod, 120... Group operation button, 1
21. Old...Lock member, 125...Detection arm. Fig. 3 129 #54v4 /12 Fig. 5

Claims (1)

[Claims] A reel stand having a reel stand formed integrally with a reel hook for driving the tape and having a means for transmitting rotational drive and rotatably provided on a substrate, and a reel wheel press-contacted to 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 is rotatably provided on a pin which is meshed with an external gear formed on the rim and is embedded in the control wheel, an internal gear meshed with the planetary wheel, and a detection wheel provided with a cam surface near the 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.