JPH0684534U - Magnetic head device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the head output from changing during forward running and reverse running. [Structure] The air gap G ₁ of the recording / reproducing head 1 is located almost at the center of the tape guides 2 and 3, and the tape guides 2 and 3 can be used without changing the sizes of the recording / reproducing head 1 and the erasing head 4.
3 of the center O ₁ and can be recorded close without matches or only a gap G ₁ of reproducing head 1, a tape guide 2,
In 3, the influence of the regulation on the tape is equalized during the forward running and the reverse running, so that the head output becomes the same. Therefore, it is not necessary to perform strict adjustment of "rotational alignment" in the rotary reverse type head, such as "height", "tilt" and "tilt" related to the magnetic head device, which can improve the productivity of the magnetic recording / reproducing apparatus. it can.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 In the present invention, a magnetic head for recording / playback (abbreviated as a recording / reproducing head in this specification) and a magnetic head for erasing only (abbreviated as an erasing head in this specification) are aligned and arranged side by side. The present invention relates to a magnetic head device (which is referred to as a reverse combination head in the present specification) which is fixed and has tape guides on both sides thereof, and enables recording and reproduction in both forward running and reverse running. More specifically, the present invention relates to improvement of the positional relationship of the air gap of the recording / reproducing head of the reverse type head.

[0002]

[Prior art]

 As a conventional reverse type combination head, for example, an azimuth non-adjustment type rotary head as shown in FIG. 9 can be cited as an example. In this head, a recording / reproducing head 104 and an erasing head 105 are installed side by side on a head holder 103, and tape guides 101, 102 for restricting the traveling position of the tape 106 in the respective heads 104, 105 are provided on both sides thereof. There is. The recording / reproducing head 104 and the erasing head 105 are housed between the left and right tape guides 101 and 102 as shown in the principle diagram shown in FIG. 10, and fixed to the head holder with an adhesive or the like after azimuth adjustment. The tape guides 101 and 102 are substantially U-shaped, and when the tape sliding contact portion 108 for slidingly contacting the tape 106, the regulation portion 109 abutting on one tape edge, and the tape edge portion on the other side are in contact with each other, the tape 106 is secured. An inclined portion 110 that gives a biasing force to the regulation portion 109 is provided. Therefore, when the tape 106 passes through the tape guide 101 (or 102), a biasing force that presses the tape 106 against the regulating portion 109 is given by the inclined portion 110, and a constant tape edge is applied to the regulating portion 109. It is provided to drive the position. Therefore, the tape guide 101, 102 regulates the deviation of the tape running position, which is mainly caused by the force received from the capstan, due to the inclination and the twist of the magnetic tape with respect to the running direction.

On the other hand, the space for accommodating the recording / reproducing head 104 and the erasing head 105 is limited by the size of the window of the cassette harf (the size of the front space of the cassette half side in which the head can be accommodated). Even including the thickness, the limit is about 13 mm. Therefore, the recording / reproducing head 104 and the erasing head 105 having a size that fits within this window size are combined, and their positions are appropriately determined in consideration of the space between the tape guides 101 and 102. At this time, the air gap G ₁ of the recording / reproducing head 104 is inevitably arranged at a position deviated from the rotation center O ₃ of the head holder 103 because of the existence of the erasing head 105. However, the tape between the two tape guides 101, 102 runs at a certain position by the action of the tape guides 101, 102 provided at both ends of the head holder 103 at the same distance from the rotation center O ₃ of the head holder 103. Therefore, in the past, it was considered that there would be no practical problem in recording and reproducing. Further, there was no particular problem in the fixed magnetic head device and the read-only rotary magnetic head device having no erasing head.

[0004]

[Problems to be solved by the device]

 However, in the case of the reverse type combination head, as shown in FIG. 12, the area where the head output coincides between the forward running and the reverse running is narrow, and the mounting angle of the head holder is slightly deviated. Since the head output is different, the problem arises that the mounting of the head holder requires precision.

As a result of various experiments and studies conducted by the present inventors on the running form of the tape with respect to this point, the tape is influenced by the capstan and causes “inclination” or “twist” in the running direction of the tape. The phenomenon that causes such problems is to be corrected by regulation by the tape guides 101 and 102, but in reality, the closer to the tape guides 101 and 102, the more the influence of the inclination of the tape 106 cannot be removed. The inventors of the present invention have come to discover that the influence of the above will remain. That is, when the behavior of the tape 106 is observed in micro units, as shown in FIG. 11, the tape 106 between the tape guides 101 and 102 on both sides actually has elongation and contraction in the plane direction. Was supported by computer analysis and experiments. When the tape guides 101 and 102 are tilted, the direction in which they are pressed against the tape guides 101 and 102 contracts and the direction in which they try to escape expands. Then, even in the recording pattern 107 magnetized perpendicularly to the tape 106 (perpendicular to the tape edge), the expansion and contraction of the tape 106 actually causes the inclination as it approaches the tape guides 101 and 102.

From this, the head output is different between the forward running and the reverse running due to the geometrical shape due to the inclination and the twist of the tape 106 received at the gap G ₁ portion of the recording / reproducing head 104. It was found that the problem was caused by the distortion of the tape and that the automatic adjustment function of the tape guide did not deteriorate. That is, even if the running position of the tape 106 is kept constant between the two tape guides 101 and 102, when the head holder 103 is rotated, the tape 106 is recorded in a state in which the expansion and contraction directions of the tape 106 are different. Since the tape 106 comes into sliding contact with the head 104, the head output is actually different between the forward running and the reverse running, in other words, the azimuth non-adjustable head actually causes azimuth loss. I have a problem.

As a result of studying such a problem, the air gap G of the recording / reproducing head is located at a position separated by the same distance from the tape guide on the tape entry side during forward running and reverse running. ₁ It has been found that arranging the tapes makes the effect of the strain on the tape guide almost the same during forward running and reverse running, and minimizes it.

However, in the conventional head structure, since the tape guide is provided at a position substantially the same distance from the rotation center O ₃ of the head holder 103, the air gap G ₁ of the recording / reproducing head 104 is connected to the tape guides 101, 102. In order to house the head holder 103 so that it is positioned on the rotation center O ₃ of the head holder 103, the erasing head 105 must be made quite small. However, there is a limit to downsizing the erasing head 105 because it requires a minimum number of windings and a coil wire diameter to give a certain erasing performance. For example, if the wire diameter is reduced to reduce the size of the erasing head 105, a vicious cycle of increasing the resistance value of the coil, the loss, and the amount of heat generation is generated, increasing the temperature of the coil and degrading the erasing performance. Therefore, in the conventional head structure, the positional relationship between the recording / reproducing head 104 and the erasing head 105 is not particularly changed, and the air gap G ₁ of the recording / reproducing head 104 is not changed during forward traveling and reverse traveling. It is difficult to place the tape at the same distance from the tape guide on the tape entry side.

An object of the present invention is to provide a magnetic head device in which head output does not change between forward traveling and reverse traveling.

[0010]

[Means for Solving the Problems]

 In order to achieve such an object, the present invention arranges a recording / reproducing head and an erasing head side by side in the tape running direction, and urges a regulation part and a tape that come into contact with one edge of the tape toward the regulation part. In a magnetic head device in which two tape guides having a tilting portion for applying a force to move are arranged, the air gap of the recording / reproducing head is positioned substantially at the center of the two tape guides.

In the present invention, one tape guide is formed between the erasing head and the recording / reproducing head, and the other tape guide is formed on the side of the recording / reproducing head opposite to the erasing head. The tape guide is formed on the erasing head itself so that the regulation portion and the inclined portion of the tape guide are located above and below the erasing gap of the erasing head, and the other tape guide is the erasing head of the recording / reproducing head. Are formed on the opposite side.

[0012]

[Action]

 Therefore, even if the recording / reproducing head is not located on the center of rotation of the head holder, the air gap of the recording / reproducing head is located at the center of the two tape guides and is the same from the tape guide on the tape entry side regardless of the running direction. By arranging the air gap of the recording / reproducing head at a position separated by a distance, the influence of distortion on the tape guide is made to be almost the same during forward running and reverse running, and it is minimized. For example, when the offset amount between the gap position of the recording / reproducing head and the rotation center of the head holder is set to 0.8 mm, which is smaller than that of the conventional general head (1.0 mm), as shown in FIG. In addition, a stable area in which the head output does not change between forward traveling and reverse traveling can be obtained in a wide range of the holder mounting angle θ, and variation in the head output when the holder mounting angle is increased can be suppressed. However, in the case of 1.5 mm, as shown in FIG. 12, the head output is completely different between the forward running and the reverse running, and the output variation is considerably large. From this, it can be understood that the smaller the offset amount of the air gap from the center between the two tape guides, the less the head output changes during forward running and reverse running.

Further, as is clear from FIG. 14 and FIG. 15, which show the results of experiments on the change that the above offset amount gives to the phase when the head holder is rotated, as is apparent from FIGS. 14 and 15, the offset amount is set to 0.8 mm. However, no change in the phase is observed, but the change in the phase appears remarkably at 1.5 mm. From this, it can be understood that the phase characteristic improves as the offset amount decreases.

[0014]

【Example】

 Hereinafter, the configuration of the present invention will be described in detail based on the embodiments shown in the drawings.

FIG. 1 is a principle view showing one embodiment of the magnetic head device of the present invention. In this magnetic head device, the recording / reproducing head 1 is arranged between the tape guides 2 and 3 on both sides, and the air gap G ₁ of the recording / reproducing head 1 is located on the center O ₁ between the tape guides 2 and 3. At the same time, the erasing head 4 is incorporated in one of the tape guides 2.

The tape guides 2 and 3 are for controlling the traveling position of the magnetic tape 5 on the recording / reproducing head 1 and the erasing head 4, and are head holders (holding the erasing head 4 and the recording / reproducing head 1). (Not shown) or integrally formed or formed as a separate member and attached. The tape guides 2 and 3 have a tape sliding contact portion 2a, 3a for slidingly contacting the tape 7, a restriction portion 2b, 3b for contacting one tape edge to restrict the tape running position, and the other tape edge. It has a substantially U-shaped concave portion composed of inclined portions 2c and 3c which generate a force for urging the tape 7 toward the regulating portions 2b and 3b when they come into contact with each other. In the case of this embodiment, one tape guide, for example, the tape guide 2 on the left side of the drawing is integrated with the erasing head 4. For example, the tape sliding contact surface of the erasing head 4 is used as the tape sliding contact portion 2a of the tape guide, and the tape sliding contact surface of the erasing head 4 is provided with the projection 5 forming the inclined portion 2c and the projection 6 forming the regulating portion 2b. It is made to project. Each of the projections 5 and 6 may be formed as a separate member from the erasing head 4 and fixed by adhesion or the like, or may be integrally formed with a member forming the tape sliding contact surface of the erasing head 4. Since it is preferable to install the tape guides 2 and 3 as wide as possible in order to stabilize the tape running, the tape guides 2 and 3 are formed at both ends of the head holder so that the maximum distance can be set. As a result, the center position O ₁ between the tape guides 2 and 3 in the present embodiment coincides with the rotation center O ₃ of the head holder 3, but the present invention is not limited to this, and the center position O ₁ of both sides. _It does not matter if ₁ and O ₃ are deviated.

In the case of this embodiment, by arranging the tape guides 2 and 3 of the same size so as to sandwich the recording / reproducing head 1, the offset amount P between the air gap G ₁ and the tape guide center O ₁ can be reduced. It is set to 0. It is most preferable to set the offset amount P to 0, but when it is not possible, it is preferably within 0.8 mm, more preferably 0. It is set within 5 mm. In the figure, reference numeral G ₂ is a gap of the erasing head 4.

With the above-described configuration, even if the erasing head 4 and the recording / reproducing head 1 are the same in size as before, the position of the air gap G ₁ of the recording / reproducing head 1 is in the left and right tape guides 2 and 3. can match with the center O ₁ between, at the time when the forward traveling and reverse traveling, since the distance to the air gap G ₁ from the tape guide of the tape entry side is matched, the regulation by the tape guides 2,3 The influence is almost the same, and the influence on the head output does not differ depending on the tape running direction. For example, when the offset amount between the position of the air gap G ₁ of the recording / reproducing head ₁ and the center O ₁ between the left and right tape guides 2 and 3 is 0.8 mm, for example, as shown in FIG. A stable area where the same head output can be obtained during drive and reverse travel can be obtained within a wide range of holder mounting angle θ, and the variation in output when the holder mounting angle θ is increased can be suppressed. However, when the offset amount is 1.5 mm, the head output becomes completely different between the forward running and the reverse running as shown in FIG. 12, and the output varies considerably. From this, it can be understood that the smaller the offset amount, the less the head output changes during forward running and reverse running. 14 and 15 show the results of experiments on changes in the phase that the offset amount gives when the head holder is rotated. As is clear from this result, when the offset amount is set to 0.8 mm, there is no particular phase change (see Fig. 15), but when it is 1.5 mm, the phase change appears significantly ( (See FIG. 14). The figure shows the degree of change in the L / R phase difference, the horizontal axis represents the mounting angle θ of the head holder in FIG. 9, and the vertical axis represents the L / R phase angle difference of 10 KHz. In this figure, the larger the inclination, the easier the phase changes.

It should be noted that the above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention. For example, in the embodiment of FIG. 1, the width of the tape guide 2 formed integrally with the erasing head 4 is formed to have the same size as the width of the erasing head 4, but the width is not particularly limited to this. As shown in FIGS. 4 to 6, an erase head 4 and a dummy block 8 having substantially the same size as that of the erase head 4 are arranged with the recording / reproducing head 1 interposed therebetween, and an inclined portion having a width narrower than that of the erase head 4 and the dummy block 8. The pair of tape guides 2 and 3 may be formed by providing the projections 5 and 5 that form the portions 2c and 3c and the projections 6 and 6 that form the restriction portions 2b and 3b. When the width dimensions of the inclined portions 2c and 3c and the regulation portions 2b and 3b are narrower than the width dimensions of the erasing head 4 and the dummy block 8, the influence of the regulation by the tape guide is not made excessive. The positions forming the tape guides 2 and 3 are not particularly limited to those shown in FIG. 1, and the tape guides may be formed at the farthest positions as shown in FIG. 4 or the closest positions as shown in FIG. It may be provided at a position, or an intermediate position between them as shown in FIG.

Further, as shown in FIG. 7, when one tape guide 2 is formed in the center of the erasing head 4 and the other tape guide 3 has a conventional tape guide shape, It suffices to provide a gap between the tape guide 3 and the dummy block 9.

Further, as shown in FIG. 8, the tape guides 2 and 3 are arranged on the right and left sides of the recording / reproducing head 1, and the erasing head 4 is arranged outside the tape guide 2, so that the erasing head 4, the tape guide 2, The recording / reproducing head 1 and the tape guide 3 are arranged in this order. In this magnetic F head device, recording it the gap G ₁ of reproducing head 1 coincides with the heart position O ₁ in the two tape guides 2,3, rotation center position O when configured as a rotary reverse type Head Does not match ₃ . However, the gain deviation and the phase difference are alleviated by the same operation as in the case of the first embodiment. In this embodiment, the rotary reverse type head is mainly described, but the same effect can be obtained with the fixed type reverse type head.

[0022]

[Effect of device]

 As is clear from the above description, in the magnetic head device of the present invention, the air gap of the recording / reproducing head is located at the center of the tape guide, so that the sizes of the recording / reproducing head and the erasing head are not changed. In addition, the center of the tape guide and the gap of the recording / reproducing head can be made to coincide with each other or to be infinitely close to each other, and the influence of the regulation imposed on the tape by the tape guide becomes equal between the forward running and the reverse running, and the head output is reduced. Will be the same. Therefore, strict adjustment of "rotational alignment" is not necessary for the rotary reverse type head, such as "height", "tilt" and "tilt" related to the magnetic head device, thus improving the productivity of the magnetic recording / reproducing device. be able to.

Further, when the erasing head and the tape guide are integrally formed, one tape guide can be omitted, it is not necessary to forcibly downsize the erasing head and the recording / reproducing head, and the head arrangement and the like can be reduced. Also has a dimensional margin.

Further, when the erasing head is arranged outside the tape guide that sandwiches the recording / reproducing head, there is no change in the shape of the parts from the conventional one while the gap of the recording / reproducing head is located in the center between the tape guides. The stability of the head output is improved simply by changing the arrangement of parts.

[Brief description of drawings]

FIG. 1 is a principle view showing an embodiment of a magnetic head device of the present invention.

FIG. 2 is an explanatory diagram schematically showing the outer shape of an erase head used in the magnetic head device of FIG.

FIG. 3 is a cross-sectional view showing an arrangement of main parts of the magnetic head device of FIG. 1 with an internal structure omitted.

FIG. 4 is a principle view showing a modified example of the magnetic head device of the embodiment of FIG.

FIG. 5 is a principle view showing another modification of the magnetic head device of the embodiment of FIG.

FIG. 6 is a principle diagram showing still another modification of the magnetic head device according to the embodiment of FIG.

FIG. 7 is a principle view of a modified example having an independent tape guide in the embodiment of FIG.

FIG. 8 is a principle view showing another embodiment of the present invention.

FIG. 9 is a front view showing an example of a conventional magnetic head device.

10 is a principle diagram showing a positional relationship between each head and the tape guide of the magnetic head device of FIG.

FIG. 11 is an explanatory diagram for microscopically observing the behavior of the magnetic tape which is guided and run by the tape guide.

FIG. 12 is experimental data showing head outputs during forward traveling and reverse traveling when the air gap of the recording / reproducing head is offset by 1.5 mm from the center of rotation of the head holder.

FIG. 13 is experimental data showing head outputs during forward traveling and reverse traveling when the air gap of the recording / reproducing head is offset by 0.8 mm from the center of rotation of the head holder.

FIG. 14 is a graph showing a change in phase at 10 kHz when the head holder is rotated by computer simulation when the recording / reproducing head is offset from the center of rotation of the head holder by 1.5 mm.

FIG. 15 is a graph showing a phase change at 10 kHz when the head holder is rotated by computer simulation when the recording / reproducing head is offset by 0.8 mm from the center of rotation of the head holder.

[Explanation of symbols]

1 Recording / reproducing head 4 Erasing head 2 Tape guide 3 Tape guide G ₁ Recording / reproducing head air gap O ₁ Center between tape guides O ₃ Position of rotation center of head holder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsunegen Hashizume 5329 Shimosuwa-machi, Suwa-gun, Nagano Sanko Seiki Co., Ltd.

Claims (3)

[Scope of utility model registration request] 1. A recording / reproducing head and an erasing head are arranged side by side in the tape running direction, and a regulating portion that contacts one edge of the tape and an inclined portion that applies a force for urging the tape toward the regulating portion. In a magnetic head device having two tape guides each having an upper recording / reproducing head, an air gap of the upper recording / reproducing head is located substantially at the center of the two tape guides. 2. One of the tape guides is formed between the erasing head and the upper recording / reproducing head, and the other tape guide is formed on the side of the upper recording / reproducing head opposite to the erasing head. The magnetic head device according to claim 1, wherein the magnetic head device is a magnetic head device. 3. One tape guide is formed on the erasing head itself so that the regulating portion and the inclined portion of the tape guide are located above and below the erasing gap of the erasing head, and the other tape guide is formed. 2. The magnetic head device according to claim 1, wherein the guide is formed on a side of the upper recording / reproducing head opposite to the erasing head.