JPH04328347A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce switches in simple constitution by using a cassette detecting switch for both detecting a cassette and detecting a miserasing preventing lug. CONSTITUTION:A cassette detecting lever 20 is turnably energized by spring force of a torsion spring 26 in interlocking with the movement of the cassette 1 so that the detecting switch 22 is on-off controlled to detect the cassette 1. When the cassette 1 is loaded into a tape driving part 24, a miserasing preventing pawl detecting lever 23 for the cassette 1 is controlled this time in its turning. As a result, it is constituted that the presence of the miserasing preventing pawl 1a is detected by an on-off changeover control on the detecting switch 22 via the cassette detecting lever 20. By this method, the cassette detection and the presence of the miserasing preventing pawl 1a can both be detected by one detecting switch 22.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording and reproducing apparatus such as a video tape recorder (hereinafter referred to as VTR), which uses a magnetic tape wound around a cassette as a recording medium.

0002

2. Description of the Related Art Conventionally, in a VTR, when a cassette 1 is inserted in the direction of the arrow from a cassette insertion opening of a cabinet (not shown) as shown in FIG. 5, a cassette holder 2 receives the cassette 1. At this time, the cassette holder 2 is slightly pressed, and the arm gear 3 is urged to rotate clockwise in the figure, and the switch lever is engaged with the engaging portion 3a of the arm gear 3. 4 is rotated counterclockwise in the figure by the spring force of the spring member 5, and the cassette detection switch 6 is turned on. Here, the control section (not shown) drives the cassette transfer drive mechanism 7 to rotate the drive gear 7a provided coaxially with the arm gear 3 in the clockwise direction in the figure, and the cassette holder 2 is moved horizontally by the guide section 8. After the cassette 1 is transferred, it is lowered and the cassette 1 is mounted on the tape drive section 9.

As shown in FIG. 6, the cassette 1 mounted on the tape drive section 9 is moved by an erroneous erasure prevention lever 10.
The presence or absence of the accidental erasure prevention claw is detected. The erroneous erasure prevention lever 10 is provided with a detection section 10a at one end corresponding to the erroneous erasure prevention claw of the cassette, and a switch operating section 10b at the other end corresponding to the erroneous erasure prevention switch. A spring member 12 is attached to this erroneous erasure prevention lever 10 so as to apply a spring force in a clockwise direction in the figure, and its detection portion 10a detects the presence or absence of an erroneous erasure prevention claw on the cassette. That is, the accidental erasure prevention lever 10 is rotated and biased by the spring force of the spring member 12 without the accidental erasure prevention claw of the cassette, and the accidental erasure prevention switch 11 is turned on using the switch operating portion 10b to enter the recording prohibition mode. Set to . Also,
When the cassette 1 has the erroneous erasure prevention claw, the detection portion 10a of the erroneous erasure prevention lever 10 comes into contact with the erroneous erasure prevention claw, so that the erroneous erasure prevention lever 10 resists the spring force of the spring member 12. It is rotated counterclockwise in the figure to be separated from the accidental erasure prevention switch 11, and the accidental erasure prevention switch 11 is turned off.

In the cassette detection switch 6, when the cassette holder 2 is slotted out, the switch lever 4 is rotated clockwise in the drawing by the engaging portion 3a of the arm gear 3 against the spring force of the spring member 5. Forced and turned off. Then, the control section (not shown) detects slot-out and stops the cassette transfer mechanism 7.

However, in the above-mentioned VTR, since the cassette detection switch 4 and the mistaken erasure prevention switch 11 are used to independently detect the cassette detection and the presence or absence of the accidental erasure prevention claw, Due to its switch configuration, it is expensive and its reliability is unsatisfactory. This is particularly an obstacle in achieving the required reliability and miniaturization of modern VTRs.

[0006]

[Problems to be Solved by the Invention] As described above, conventional magnetic recording and reproducing devices use separate switches for cassette detection and accidental erasure prevention claw detection, which makes them expensive and , which was not satisfactory in terms of reliability.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a magnetic recording/reproducing device that has a simple configuration, reduces the number of switches, reduces costs, and improves reliability. purpose.

[0008]

[Means for Solving the Problems] The present invention detects the transferred cassette in a magnetic recording/reproducing device in which a cassette wound with magnetic tape is transferred and attached to/detached from a tape drive unit. a cassette detecting member that is movably provided; a claw detecting member that is rotatably provided corresponding to the accidental erasure prevention claw of the cassette mounted on the tape drive unit; and the cassette detecting member and the claw detecting member. An elastic member that elastically connects each other, a detection switch whose switching is controlled by the cassette detection member, and a rotation control of the cassette detection member by regulating the position of the claw detection member, and the cassette detection member switches the detection switch. cassette detecting means for controlling and detecting a cassette being transferred; controlling the rotation of the claw detecting member to switch and control the detection switch via the cassette detecting member; The device also includes claw detection means for detecting the presence or absence of a prevention claw.

[0009]

[Operation] According to the above structure, the detection switch performs on/off switching control by controlling the rotation of the cassette detection member by the cassette detection means in conjunction with the transfer of the cassette, thereby detecting the cassette. When the cassette is loaded into the tape drive section, the pawl detection means rotates the pawl detection member depending on whether or not the cassette has an accidental erasure prevention pawl, and the detection switch is activated again via the cassette detection member. The on/off switching control is performed to detect the presence or absence of the accidental erasure prevention claw. This makes it possible to detect the cassette and detect the presence or absence of the erroneous erasure prevention claw by using one detection switch in common.

0010

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the main parts of a magnetic recording and reproducing apparatus according to an embodiment of the present invention. In the figure, reference numeral 20 denotes a cassette detection lever.
It is rotatably provided via the. This cassette detection lever 20 has a switch drive section 20a that is connected to a detection switch 22.
The switching section 22a is provided corresponding to the switching section 22a.
A spring engaging portion 22b is formed correspondingly. For example, as explained in FIG.
The locking mechanism (not shown) is unlocked in conjunction with the activation of the locking mechanism, and the locking mechanism is set in a freely rotatable state.

Reference numeral 23 in the figure denotes an erroneous erasure prevention claw detection lever, which is provided corresponding to the erroneous erasure prevention claw 1a of the cassette 1 mounted on the tape drive unit 24, as shown in FIG. The erroneous erasure prevention claw detection lever 23 has an intermediate portion rotatably formed via a shaft 25, and a detection portion 23a is formed at one end thereof corresponding to the erroneous erasure prevention claw 1a of the cassette. An operating section 23b is provided at the other end of the accidental erasure prevention claw detection lever 23 in correspondence with the switch driving section 20a of the cassette detection lever 20. Further, the intermediate portion of a torsion spring 26 is attached to the shaft 25 of the accidental erasure prevention claw detection lever 23. One end of the torsion spring 26 is engaged with a spring engaging portion 23c provided on the accidental erasure prevention pawl detection lever 23, and the other end is engaged with the spring engagement portion 20b of the cassette detection lever 20. 23 and the cassette detection lever 20 are engaged so as to bias them in a direction in which they come into contact with each other.

Further, reference numeral 27 in the figure is a connect lever, which is rotatably provided via a shaft 28 in correspondence with the erroneous erasure prevention claw detection lever 23. The connect lever 27 has an engaging protrusion 27a formed at one end corresponding to the erroneous erasure prevention claw detection lever 23, and a locking portion 27b formed at the other end corresponding to the reel clutch cam 29. The reel clutch cam 29 is rotatably provided via a shaft 30,
A locking portion 29a is provided on the periphery thereof in correspondence with the locking portion 27b of the connect lever 27. The reel clutch cam 29 is rotationally controlled in conjunction with a tape loading mechanism (not shown), and its locking portion 29a engages the connect lever 27.
is rotated counterclockwise in the figure, and the connect lever 2 is
The engagement protrusion 27a at 7 restricts the rotation of the accidental erasure prevention claw detection lever 23 in the counterclockwise direction in the drawing. Then, when the reel clutch cam 29 is rotated again and its locking portion 29a is separated from the locking portion 27b of the connect lever 27, the lock of the connect lever 27 is released and the connect lever 27 can be rotated. Free state.

In the above configuration, before the cassette loading shown in FIG. 1, the cassette detection lever 20 is regulated in position by the locking mechanism (not shown) at the position shown in FIG. 1 as described above, and the detection switch 22 is turned off. There is. Then, when the cassette is inserted, the locking mechanism (
(not shown) is activated and the lock is released, and the cassette detection lever 20 is urged to rotate clockwise in the figure by the spring force of the torsion spring 26, and the switch driving section 20a of the cassette detection lever 20 is activated to release the lock. Activate the switch to turn it on. Here, the control section (not shown) detects the insertion of the cassette 1 and moves the cassette transfer mechanism 7 (see FIG. 5)
The inserted cassette 1 is transferred to the tape drive section 24, and is mounted as shown in FIG.

In this cassette 1, the detection portion 23a of the erroneous erasure prevention lever 23 is opposed to the erroneous erasure prevention claw 1a. Here, the above tape loading mechanism (not shown)
is activated, the magnetic tape of the cassette 1 is pulled out, and the tape is loaded. In conjunction with this, the reel clutch cam 29 is rotated counterclockwise in the figure, and the locking portion of the connect lever is disengaged from the engagement protrusion of the reel clutch cam, allowing the connect lever to rotate. The erroneous erasure prevention claw detection lever 23 is biased to rotate clockwise in the figure by the spring force of the torsion spring 26. At this time, if the accidental erasure prevention claw 1a of the cassette 1 is removed, the accidental erasure prevention lever 23 is rotated in the same direction (see FIG. 3), and its operating portion 23b drives the switch of the cassette detection lever 20. The detection switch 22 is switched from the on state to the off state by pressing the portion 20a. Here, the control section (not shown) detects the absence of the accidental erasure prevention claw 1a and sets the mode to the recording prohibition mode.

Furthermore, when the erroneous erasure prevention claw 1a of the cassette 1 is present, the erroneous erasure prevention lever 23 is moved as shown in FIG.
When the detecting section 23a comes into contact with the erroneous erasure prevention pawl 1a and its rotation is restricted, the operating section 23b is separated from the switch driving section 20a of the cassette detecting lever 20. Therefore, the cassette detection lever 20 is urged to rotate clockwise in the figure by the spring force of the torsion spring 26.
The switch driving section 20a presses the switching section 22a of the detection switch 22 to keep it in the on state. Here, the control section (not shown) detects the presence of the accidental erasure prevention claw 1a, and sets the recording mode in response to the recording operation by the operator.

When the cassette 1 loaded in the tape drive section 24 is slotted out, the loaded tape is first unloaded and stored in the cassette. Then, reel clutch cam 2
9 is reversed, and its locking portion 29a engages the connect lever 2.
7 is locked, and the position of the accidental erasure prevention claw detection lever 23 is regulated at the position shown in FIG. Here, the switching portion 22a of the detection switch 22 is pressed by the switch driving portion 20a of the cassette detection lever 20 as described above, and is set to the on state. Next, the cassette transfer mechanism (not shown) is reversed, and the cassette 1 is ejected and slotted out. Then, the cassette detection lever 20 is regulated in position by the locking mechanism (not shown) at the position shown in FIG. Set to off. Here, the control section (
(not shown) detects slot-out of the cassette 1 and stops a cassette transport mechanism (not shown). Note that the detection switch 22 may be configured to be turned off when a cassette is detected, for example, instead of being turned on when a cassette is detected.

As described above, in the magnetic recording/reproducing apparatus, the cassette detection lever 20 is rotationally biased by the spring force of the torsion spring 26 in conjunction with the transfer of the cassette 1, and the detection switch 22 is controlled to turn on/off. te cassette 1
When the detection is performed and the cassette 1 is installed in the tape drive section 24, the rotation of the erroneous erasure prevention claw detection lever 23 is controlled by the connect lever 27 depending on the presence or absence of the erroneous erasure prevention claw 1a of the cassette 1. the above cassette detection lever 20.
The detection switch 22 is controlled to be turned on and off via the holder to detect the presence or absence of the erroneous erasure prevention claw 1a. According to this, it becomes possible to detect the cassette and detect the presence or absence of the accidental erasure prevention claw by using a single detection switch 22, which simplifies the switch configuration and improves the reliability of the detection. Moreover, the price can be reduced.

In the above embodiment, the cassette detection lever 20 is linked to the arm gear 3 to release the lock, and the accidental erasure prevention claw detection lever 23 is linked to the tape loading mechanism (not shown) to release the connection lever 27. and the reel clutch cam 29 was used to control the rotation.
Various configurations are possible without being limited to this. Therefore,
It goes without saying that the present invention is not limited to the above embodiments, and that various modifications can be made without departing from the gist of the invention.

[0020]

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide a magnetic recording and reproducing device that has a simple configuration, reduces the number of switches, reduces costs, and improves reliability. Can be done.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the main parts of a magnetic recording and reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing the operating state of FIG. 1;

FIG. 3 is a diagram showing the operating state of FIG. 1;

FIG. 4 is a diagram showing the operating state of FIG. 1;

FIG. 5 is a diagram showing a cassette detection mechanism of a conventional magnetic recording/reproducing device.

FIG. 6 is a diagram showing the erroneous erasure prevention claw detection mechanism of FIG. 5;

[Explanation of symbols]

20...Cassette detection lever, 21, 25, 28, 30...
Shaft, 22...detection switch, 23...accidental erasure prevention claw detection lever, 24...tape drive unit, 26...torsion spring, 27...connect lever, 29...clutch cam.

Claims (1)

[Claims] 1. In a magnetic recording and reproducing device in which a cassette wrapped with magnetic tape is transferred and attached to and detached from a tape drive unit, a cassette detection member rotatably provided is used to detect the transferred cassette. a claw detection member that is rotatably provided in correspondence with an accidental erasure prevention claw of the cassette mounted on the tape drive unit; and an elastic member that elastically connects the cassette detection member and the claw detection member to each other. , a detection switch whose switching is controlled by the cassette detection member and a rotational control of the cassette detection member by regulating the position of the claw detection member, and a switching control of the detection switch by the cassette detection member to detect the transferred cassette. cassette detection means for detecting, and rotationally controlling the claw detection member to switch and control the detection switch via the cassette detection member;
1. A magnetic recording and reproducing apparatus comprising: claw detection means for detecting the presence or absence of the accidental erasure prevention claw attached to a tape drive section.