JPH0414663A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain miniaturization and light weight of the device by fixing a post to be fixed in contiguity with a rotary cylinder parallel to a cylindrical shaft of the rotary cylinder, securing a gap between the rotary cylinder and the post and moreover evading contact with a magnetic head protruded from a cylindrical surface of the rotary cylinder and a slant post immediately before completion of loading. CONSTITUTION:In the case of attaining miniaturization and light weight of the device by applying a 4-head type small size cylinder system to a magnetic recording and reproducing device having PCM sound tracks in addition to video tracks at a standard winding angle of 221 deg. similar to an 8mm video format, a gap between the rotary cylinder and 1st and 2nd posts can be set as about 0.1mm, and by providing a run-off part from a video head in one part of the 1st and 2nd posts respectively, the head can be prevented from being damaged in case of contact between the 1st or the 2nd post and the magnetic head.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention involves winding and running a magnetic tape around a rotating cylinder to which a magnetic head is attached, thereby achieving sliding contact between the magnetic head and the magnetic tape, and thereby transmitting video signals, etc. The present invention relates to a magnetic recording and reproducing device such as a video tape recorder that records and reproduces a predetermined information signal.

(Prior art) In recent years, magnetic recording and reproducing devices such as cassette-type video tape recorders have become smaller and lighter, and in camera-integrated video tape recorders, the diameter of the cylinder is set to 2/3 of that of standard types. Types using small diameter cylinders with four heads with a winding angle of 285 degrees are becoming mainstream.

The configuration of a conventional magnetic recording/reproducing device will be described below with reference to FIGS. 15 to 18.

FIG. 15 is a plan view of a conventional magnetic recording/reproducing device.

In FIG. 15, 101 is a cassette containing a reel wound with magnetic tape, and 102 is a magnetic head 103a to 103a.
It is a rotating cylinder in which 103d is divided into 90' parts on the circumference.

Reference numerals 104a and 104b are tape guide posts, which are placed inside the cassette opening (indicated by broken lines) when a cassette is installed, and when a cassette detection switch (not shown) detects that the cassette is installed, the tape guide posts 104a,
104b performs tape loading along the path indicated by the arrow and is fixed at a predetermined position. 105a and 105b are inclined posts, and the inclined post 105a is fixed to the same base as the tape guide post 104a.

Further, the inclined post 105b is fixed on the substrate 106. 107 is a capstan that runs the magnetic tape 108 at a predetermined speed, and by pressing the magnetic tape 108 onto the capstan 107 with a pinch roller 109, the rotational force of the capstan 107 is transmitted to the magnetic tape 108, and the magnetic tape 108 is The tape 108 is configured to be transported at a predetermined speed.

FIG. 16 is a plan view of a rotating cylinder of a conventional magnetic recording/reproducing device, and FIG. 17 is a front view of the rotating cylinder. Figure 18 shows head switching when a 4-head type small diameter cylinder is used.The magnetic heads are 103a → 103d → 103C → 103b → 10
The data are recorded or played back in the order of 3a.

The wrapping angle of the rotating cylinder is 285°, which is 3/2 times that of the standard type (190°).

(Problem to be Solved by the Invention) However, in the above conventional configuration, in a standard such as the 8FIn video format, which has a standard wrapping angle of 221° and has a PCM audio track in addition to the video track, the conventional configuration does not work. If we were to reduce the size and weight of the equipment by using one type of 4-head type small-diameter cylinder as described above, we would like to reduce the winding angle to 3.
31.5' (221° x 372 = 331.5a), so that the clearance between the rotating cylinder and the tape guide post is necessarily very small (
The problem is that such precision cannot be easily obtained during the manufacturing process.

In addition, for the loading path of the tape guide post that pulls the magnetic tape from inside the cassette to the outside of the cassette, ensure the distance between each post and cylinder so that each post does not come into contact with the rotating cylinder or magnetic head during the loading operation. There is a need to keep it.

The purpose of the present invention is to solve the above problems by fixing a post that is fixed close to the rotating cylinder parallel to the cylindrical axis of the rotating cylinder, thereby securing a gap between the rotating cylinder and the post, and further improving the loading speed. A magnetic head protruding from the cylindrical surface of the rotating cylinder just before completion,
It is an object of the present invention to provide a magnetic recording and reproducing device in which the tilted post can be brought close to the rotating cylinder by avoiding contact with the tilted post, and as a result, the device can be made smaller and lighter.

(Means for Solving the Problems) The magnetic recording and reproducing device of the present invention draws a magnetic tape out of the cassette from a cassette in which a rotating cylinder equipped with a magnetic head and a reel wound with magnetic tape is built into the rotating cylinder. The magnetic tape is wound around the magnetic tape at a predetermined angle, and the magnetic head has a relief part near the rotational movement of the magnetic head on the rotating cylinder.

(Function) With the above configuration, it is possible to avoid contact between the inclined post, which is fixed in close proximity to the rotating cylinder, and the magnetic head, which is provided on the rotating cylinder and slightly protrudes from the cylindrical surface of the cylinder. Become.

(Embodiment) A tape loading mechanism of a magnetic recording/reproducing apparatus according to an embodiment of the present invention will be explained based on FIGS. 1 to 14.

First, the tape loading means will be explained.

FIG. 1 shows a schematic plan view of an embodiment of the present invention. In the figure, reference numeral 1 denotes a rotating cylinder, on which a magnetic tape 3 pulled out from a cassette 2 mounted in a magnetic recording/reproducing apparatus is wound in an M-shape over a range of 331.5 degrees on its outer peripheral surface. The rotating cylinder 1 has a set of four magnetic heads 4a.

4b, 4c, and 4d have their tips slightly protruding from the outer periphery of the cylinder, and are arranged on the circumference divided by 90 degrees. A loading ring 5 is rotatably provided around the outer periphery of the rotary cylinder 1 by a ring roller 6 for guiding the magnetic tape 3 pulled out from the cassette 2 so as to be wound around the outer peripheral surface of the rotary cylinder 1. The loading ring 5 holds a second post 8b, which is an inclined post, and a tape guide post 9d, which are fixed in parallel with the one-turn cylinder l when tape loading is completed, via a rod 7 provided so as to be able to rotate freely once. A second post holder 10b is provided.

The loading ring 5 is driven by a loading operation drive motor (hereinafter referred to as loading motor) 11, and is connected to a rotating arm 12 which forms a helical gear and a transmission gear 1.
Rotation operation is performed via 3a and 13b. The second post holder 10b operates to wind the magnetic tape 3, which has been passed around the second post 8b and the tape guide post 9d, around the rotating cylinder 1 from a counterclockwise direction along the loading guide T14. . A first post holder 10a holds a first post 8a and a tape guide post 9c, which are inclined posts that are fixed parallel to the rotary cylinder 1 when tape loading is completed. A loading guide S 15 is provided on the first substrate 16 and includes a first gear 17 . 18(
2 and 3), arrow A points over the surface of the first substrate 16.

8 A loading plate that moves in both directions (FIG. 2) and a rotating shaft 20 of a second gear 19 that meshes with the first gear 17, and a roller that rolls in contact with the inner surface 16' of the first substrate 16. 21, and a connecting shaft 23 that connects with the second substrate 22. Reference numeral 24 denotes a second plate 18 mounted on the loading plate 18 so as to be rotatable about a single rotation shaft 20 formed of a sheet metal bent in a U-shape.
This is the loading arm.

The second loading arm 24 is provided with an arm portion and a third gear 25 that meshes with the second gear 19, and a rotating shaft 27 of the first loading arm 26 that supports the first post holder 10a is installed. ing.

Reference numeral 28 denotes a fourth gear, to which a unidirectional biasing force is always applied by a compression spring 29. As the loading plate 18 moves in the direction of arrow A (FIG. 2), the fourth gear 28 meshes with the second gear 19, completing tape loading and fixing the first post holder 10a in a predetermined position. When the second gear 19 and the arrow A
It is configured to slide in the direction.

Next, a mechanism for pulling out the tape guide post 9f will be explained (see FIGS. 1 to 4).

A tape guide post arm 31 having a one-turn fulcrum 30 is mounted on the second board 22, and the tape guide post arm 31 is equipped with a guide 32 provided on the first board 16 and a leaf spring 33. A cam pin 34 is provided that corresponds to the guide groove 32 that is formed.

Next, the tension regulator mechanism will be explained using FIG. 4.

A tension arm 37 is provided on the second substrate 22 and is rotatable about a rotation fulcrum 36, which holds a tension post 35 that detects tape tension during recording and reproduction and maintains a constant tension. There is.

A tension band 39 is attached to the tension arm 37 and is wound around a brake drum portion 38a formed on the reel stand 38 to apply braking force to the reel stand 38. Reference numeral 40 shown in FIG. 1 is a tension post release cam fixed to the first board 16, and includes a cam portion 40a that releases the tension arm 37 during loading and unloading, and a cam portion 40a that releases the tension arm 37 during REV and REV.
It consists of a cam portion 40b that prevents the return of the cam.

Next, the cassette mounting section and the means for moving the cassette in and out of the cabinet will be explained.

A cassette mounting part into which the cassette 2 is mounted is configured on the side facing the rotating cylinder 1, and this cassette mounting part is configured to accommodate the mounted cassette 2 in the opening of the cassette 2. 2nd to move to
A cassette holder is provided which is held on the substrate 22 (FIG. 4) and operates to raise and return the tape cassette 2 mounted as described above to the cassette insertion/ejection port side of the main body of the apparatus at the time of injection. On the second substrate 22,
- A pair of reel stands 38, 41 are provided, and the cassette 2 is wound with the magnetic tape 3. Reel stands 38 respectively correspond to the tape supply reel 43 and the tape take-up reel 44.
．． 41 and is installed. In addition, the second substrate 22
, elongated holes 22a to 22d corresponding to the guide pins provided on the first substrate 16 and cam grooves 61 corresponding to the cam pins 46 of the rotating arm 12 formed with helical gears.
is formed to direct the rotational movement of the rotational arm 12 to the second substrate 2.
2, and is configured to give the attached cassette 2 back and forth reciprocating motion toward the rotary cylinder 1.

Next, the tape pass will be explained.

In FIG. 5, the magnetic tape 3 pulled out from the tape supply reel 43 is transferred from the cassette 2 to the tape guide post 9a, the tension post 35. Tape guide post 9b
, 9c, and is pulled out horizontally to the cassette 2 until it reaches the first post 8a. After pulling out the magnetic tape 3 from the opening of the cassette 2, the first post 8a and the second post 8b are fixed on the first substrate 16 and are arranged parallel to the rotating cylinder 1 in its axial direction. There is. Magnetic tape 3 wrapped around rotating cylinder 1
descends along the lead surface formed on the rotating cylinder 1, and connects the second post 8b and the tape guide post 9d.
After that, the magnetic tape gradually rises, passes through a capstan 49 that drives the magnetic tape 3 at a constant speed by being pressed against a pinch roller 48, and reaches the tape guide post 9e.

At the position of this tape guide post 9e, the magnetic tape 3 is
The tape supply 2 spring removal reel has returned to the height of 43.44. Thereafter, the twist of the magnetic tape 3 is eliminated by the third post 8C provided at an angle with respect to the magnetic tape 3, and the magnetic tape 3 is moved to the tape guide post 9f.
The tape is then wound onto a tape take-up reel 44.

Furthermore, the first post 8a and the second post 8b will be explained using FIG. 8 and FIGS. 9-1 to 9-3.

FIG. 8 is a top view of a first post 8a and a second post 8b fixed in parallel with the rotating cylinder 1,
FIG. 9-3 is a side view of the rotating cylinder 1 and the second post 8b. First and second bosses 8a, 8
In b, there is a relief part 8 for securing the distance between the magnetic heads 4a to 4d attached to the lower part of the rotary cylinder 1.
a', 8 b' are provided, and 10,000-first or second
The magnetic heads (4a to 4d) are constructed to avoid damage when they come into contact with the bosses 8a, 8b and the rotating cylinder 1.

Also, the magnetic tape 3 overlaps the relief parts 8a' and 8b' (Fig. 9-3), but the magnetic heads 48 to 8b overlap.
Since the height is close to the rotational height of the magnetic tape 4b, it is not affected by twisting of the magnetic tape.

The relief portions 8a' and 8b' also function to suppress vibrations caused by collisions between the magnetic heads 48-4d and the magnetic tape 3 during tape running.

By finely adjusting the width of 8b', jitter can be significantly improved.

Next, the configuration of a four-head rotary head cylinder will be described. In addition, the tape format of 8m + video is shown in Figure 6 (a)? Shown in (b).

As is well known, in the 8 countries video format, a 28.5-minute PCM audio track is added in addition to the track section (180° minutes) for recording screen signals, so the winding angle of the standard cylinder (2-head type) is 221". In order to downsize the rotating cylinder while adhering to this standard, the 4-head /1) diameter cylinder type, as shown in Figure 7, has 4 rotary cylinders. Magnetic heads 4a, 4b.

4c and 4d in order to perform recording and reproduction, the tape winding angle around the rotary cylinder 1 is 221.
331.5", which is 3/2 times 331.5". Furthermore, the magnetic tape 3 wound around the rotating cylinder 1 is configured so that the tapes overlap unless the magnetic tape 3 is folded back at an acute angle (8 m/m standard in the case of).

Then, once the tape loading is complete.

A first post 8a fixed parallel to the rotating cylinder 1
8 and 9 for the method of fixing the second post 8b.
This will be explained with reference to Figure-1 and Figure 9-2. 8th
The figure is a schematic plan view showing the arrangement of a stopper pin 50 for accurately fixing the first post 8a and the second post 8b in predetermined positions, and FIG. 9 is a front view thereof. For reference, FIG. 14 is a perspective view of the first substrate 16 on which stopper pins are erected.

In FIGS. 8, 9-1 and 9-2, the stopper pin 50 is placed on the rotating cylinder 1 on the first substrate I6.
It is planted parallel to the central axis of the cylindrical surface.

1st. The first post 8a and the second post 8b attached to the second post holders 10a and 10b are connected to the cylindrical portion of the lower cylinder 51 (the diameter is larger than the cylinder diameter by the step difference forming the lead).

It is fixed so as to be directly inserted with the stopper pin 50.

With this configuration, the two-dimensional positional accuracy of the first post 8a and the second post 8b with respect to the rotary cylinder 1 can be improved by making them both contact the cylindrical portion of the lower cylinder 51 of the rotary cylinder 1, and Since the stopper pin 50 is placed perpendicularly on the first substrate 16 to which the holder is attached, highly accurate positioning is possible.

Next, the pinch roller pressure contact mechanism will be explained.

In FIG. 1θ, reference numeral 52 denotes a pinch arm that rotates about a rotating shaft 53 vertically set on the first substrate 16 as a fulcrum. The pinch roller 48 is rotatably mounted around an inclined pinch roller shaft 54 so that the pinch roller 48 can be stored in the cassette opening during unloading. It is set to be parallel to the capstan 49 when the capstan 49 is pressed.

In FIG. 11, a toggle is formed by a pinch crimp lever A55 and a pinch crimp lever B56. 57 is a fixed shaft provided on the first substrate 16. The pinch crimping lever A55 has a pinch crimping spring 58.
One end of the pinch crimp spring 58 is hung, and the other end of the pinch crimp spring 58 is hung on a spring hook pin 60 provided on the pinch crimp rod 59.

The pinch crimping rod 59 is configured to be kicked by a cam pin 46 provided on the rotating arm 12 so that the biasing force of the pinch crimping spring 58 is transmitted as the pressing force of the pinch roller 48 . 61' is the first substrate 1
This is a guide pin provided on 6.

The operation of the magnetic recording/reproducing apparatus configured as described above will be explained below.

FIG. 12 is a plan view showing the cassette mounting device moved outside the cabinet. In this state,
First, when cassette 2 is installed in the device as shown by the dotted chain line, a detection switch (not shown) that detects the installation of the cassette
The cassette device is detected and the load jig motor 1 is activated.
The worm 62 rotates and is attached to the motor 11.
The rotating arm 12 is rotated clockwise. This rotating force is transmitted to the loading ring 5 via the transmission gears 13a and 13b, and the magnetic tape 3 stored in the opening of the cassette 2 is moved by the tape guide post 9d provided on the second post holder 10b. , and is pulled out to a predetermined position outside the cassette 2 (FIG. 1), and is securely locked by the fixing means (FIGS. 8 and 9).

Simultaneously with the magnetic tape pulling operation of the second post holder 10b described above, the cam pin 46 provided on the single rotation arm 12 moves along the cam groove 61 formed on the second substrate 22, and the rotation arm 12 rotates clockwise, the second board 22 opens the elongated holes 22a, 22b,
22c, 22d, the cassette 2 is moved in the direction of the rotary cylinder 1.

When the cassette 2 moves to a predetermined position (FIG. 1), the cam pin 46 has moved to the end of the arc portion of the cam groove 61, and the cassette 2 stops.

Next, the tape loading operation using the first post holder 10a will be explained based on FIGS. 1 to 3 and FIGS. 12 and 13.

The clockwise rotation of the rotation arm 12 causes the loading plate 18 to move integrally with the movement of the second substrate 22 toward the rotation cylinder 1 . Along with this movement, the second gear 19 installed on the loading plate 18 is rotated clockwise by the first gear 17, and the third gear 2 that meshes with the second gear 19 is rotated clockwise by the first gear 17.
The first loading arm 26 with 5 is rotated counterclockwise. By these operations, the first post holder 10a is moved so as to pull out the magnetic tape 3 from inside the opening of the cassette 2 to the outside of the cassette. Further, in the first post 8a provided on the first post holder 10a, the movement locus of the tape guide post 9c follows the loading guide S15, and the one end 26' of the first loading arm 26 By performing the motion, the trajectory of arrow A shown in FIG. 13 is followed. By the above-mentioned operation, the first post 8 in the middle of loading
A sufficient distance can be secured between the rotary cylinder 1 and the first post 8a, and the first post 8a can be brought close to the rotary cylinder 1 just before loading is completed.

Further, the rotation shaft 27 of the first loading arm 26 provided on the second loading arm 24 is restricted from rotating around the first rotation shaft 20 by a rotation prevention guide 63 during the loading operation. , the rotation restriction is released when the first post holder 10a moves to the position shown in FIG. With the above-mentioned configuration, the second loading arm 24 and the first loading arm 26 absorb variations in the distance between the one end 26' of the tenth loading arm 26 and the rotating shaft 20 when the first post holder 10a is pressed into contact with the first post holder 10a. and one rotation axis 20. One end 26' of the first loading arm 26 and the first post 8a constitute a toggle, which generates a force that presses the shaft of the tape guide post 9c against the stopper 64. Note that during crimping, the first and second loading arms 26, 24 operate substantially as one unit. Further, the compression force of the first post boulder 1Oa is generated by the compression spring 29.

Next, the pinch roller pressing operation will be explained.

When tape loading is completed and the loading motor 11 continues to rotate, the cam pin 46 provided on the rotating arm 12 reaches the end of the arc portion of the cam groove 61 provided on the second substrate 22. At this time, pull the pinch crimping spring 58 (Fig. 11) and pinch crimping lever A.
, B55.56, the pinch crimp rod 59 is moved toward the upper fabric in FIG. 11 so as to press the pinch roller 48 against the capstan 49. The above-described configuration makes it possible to transport the magnetic tape 3 at a predetermined speed.

Next, the operation of pulling out the tape guide post 9f will be explained.

Tape guide post 9f (Fig. 1, Fig. 4, Fig. 12)
The tape guide post arm 31 holding the tape guide post arm 31 is installed on the second substrate 22, and as the second substrate 22 moves in the direction of the rotating cylinder 1 from the state shown in FIG. Arm 3I is rotated clockwise.

When the second board 22 completes its movement, the tape guide post 9f is moved to the stopper 65 provided on the first board 16.
The pressing force is such that the biasing force of the leaf spring 33 acts on the cam pin 34. The stopper 65 has a surface 65' that is parallel to the magnetic tape 3 pulled out from the third post 8c. A portion 31' (the first
(Fig.) is configured so that the magnetic tape 3 is in contact with the third post (inclined post) 8c, so that even if the stop position of the second board 22 varies, the wrapping angle of the magnetic tape 3 around the third post (inclined post) 8c remains constant. It can be kept to

(Effects of the Invention) According to the present invention, a 4-head type small-diameter cylinder single-type magnetic recording and reproducing device having a standard winding angle of 221° and a PCM audio track in addition to a video track, such as an 8ae video format, can be used. In order to reduce the size and weight of the device, the gap between the rotary cylinder and the first and second posts can be set to about 0.1m. By providing a part of the video head with a relief part, it is possible to avoid damage to the head even if the first or second post and the magnetic head come into contact with each other.

Furthermore, by adjusting and changing the range of the relief parts of the first and second posts, the stiffness of the magnetic tape can be reduced, and tape vibrations caused by collision between the tape and the magnetic head during recording or reproduction of symbols can be suppressed. is possible. This makes it possible to reduce jitter, and its practical effects are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a magnetic recording/reproducing device according to an embodiment of the present invention, FIG. 2 is a plan view of the main part of the device, FIG. 3 is a side view of the main part of the device, and FIG. A plan view showing the configuration of the board,
Figure 5 is a perspective view showing the tape bus of the same device, Figure 6 (a
L (b) is a schematic diagram showing the standard winding specifications for an 8m/+ video tape recorder, FIG. 7 is a schematic diagram showing the winding specifications when using a 4-head small-diameter cylinder for an 8-layer/1I video tape recorder, FIG. 8 is a plan view of a main part of a magnetic recording/reproducing device according to an embodiment of the present invention, FIG. 9 is a front view of a main part of the same device,
Fig. 10 is a side view of the pinch crimping arm of the same device, Fig. 11 is a plan view of the pinch roller-crimping mechanism of the sensing device, Fig. 12 is a plan view of the same device at the unloading position, and Fig. 13 is the same device. Fig. 14 is a perspective view of the first substrate of the device, Fig. 15 is a schematic plan view of a conventional magnetic recording/reproducing device, and Fig. 16 shows the rotating cylinder wound state of the device. A schematic plan view, FIG. 17 is a front view of the rotary cylinder shown in FIG. 16, and FIG. 18 is a schematic diagram showing the winding specifications of the device. 1...Rotating cylinder, 2...Cassette, 3
...magnetic tape, 4a, 4b, 4c, 4d
...Magnetic head, 5...Loading ring, 6...Ring roller, 7...Rod, 8a...First post, 8b...Second post, 8C...Third post. 98-9f... Tape guide post, 10a... First post holder, 10b... Second post holder, 11... Loading motor, 12... Rotating arm, 13a, 13b... Transmission gear, 14...
Loading guide T, 15... Loading guide S. 16... first board, 17... first gear, 18.
... loading plate, 19... second gear,
20.27.53... Rotating shaft, 21... Roller, 22... Second substrate, 23... Connection shaft, 2
4... Second loading arm, 25... Third gear, 26... First loading arm, 28...
・Fourth gear, 29...Crimp spring, 30...Rotation fulcrum, 31...Tape guide post arm, 32-
... Guide, 33 ... Leaf spring, 34.46 ... Cam pin, 35 ... Tension post, 36 ... Rotation fulcrum, 37 ... Tension arm, 38 ... Reel stand. 38a... Brake drum part, 39... Tension band, 40... Tension post release cam, 41...
... Reel stand, 43... Tape supply reel, 44.
...Tape take-up reel, 48... Pinch roller-4
9... Capstan, 50... Stopper pin, 5
1... Lower cylinder - 52... Pinch arm, 54.
... Pinch roller shaft, 55... Pinch pressure bonding lever A, 56... Pinch pressure bonding lever B, 57... Fixed shaft, 58... Pinch pressure bonding spring, 59... Pinch pressure bonding rod, 60.・・Spring hook pin, 61'
...Guide pin, 62... Worm, 63...
Rotation prevention guide, 64.65...stopper 65'
...Parallel surfaces. Patent applicant Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] A magnetic tape is pulled out of the cassette from a cassette containing a rotating cylinder equipped with a magnetic head and a reel wound with magnetic tape, and the magnetic tape is wound around the rotating cylinder at a predetermined angle. A magnetic recording/reproducing device characterized in that the magnetic head has a post having a relief portion for the magnetic head in the vicinity of where the magnetic head rotates on the rotating cylinder.