JPH0573728U - Magnetic head device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a magnetic head device having a tape guide in which a widthwise end portion of a magnetic tape is not bent and a wrinkle is not generated in a central portion of the magnetic tape. [Structure] A tape guide 21 is provided with a sliding contact surface 23 that is in sliding contact with the magnetic recording surface of the magnetic tape 3, and a pair of guide portions 25 that project from the sliding contact surface 23 and respectively guide both ends in the width direction of the magnetic tape 3. Have. The protrusion 22 is formed so as to face each of the pair of guides 25.
A groove 24 is formed between the sliding surface 2 and the sliding contact surface 23 so as to sandwich the end portion in the width direction of the magnetic tape 3. [Effect] The widthwise ends of the magnetic tape are not broken, and wrinkles do not occur at the center of the magnetic tape.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head device in which a tape guide is provided at both ends of a magnetic head in a magnetic tape sliding direction.

[0002]

[Prior Art]

 In a magnetic head device configured to write and read signals by sliding a magnetic tape on the magnetic head, it is important that the head gap between the magnetic tape and the magnetic head is in close contact, and the close contact between them is not good. Then, it may cause deterioration of magnetic recording characteristics.

In order to bring the magnetic tape into close contact with the head gap of the magnetic head, it is necessary to apply back tension to the magnetic tape and press the magnetic tape against the front surface of the magnetic head.

FIG. 7 shows a magnetic tape loading mechanism used in one type of home video tape recorder (VTR).

In FIG. 7, 1 is a supply reel housed in a tape cassette, 2 is a take-up reel, respectively, and the magnetic tape 3 is pulled out from the tape cassette at the time of loading and half-circled around the rotary head 5 of the video tape recorder. It is designed so that it can be wrapped around.

Further, in the configuration of FIG. 7, a back tension post 6, an erasing head 7, an impedance roller 8, a loading pin 9 and the like are provided between the supply reel 1 and the rotary head 5, and the rotary head 5 and A loading pin 10, a roller 11, a voice erasing head 12, a voice control head 13, a post 14, a pinch roller 15, a cap stun 16 and the like are provided between the take-up reel 2.

Further, the loading pins 9 and 10 serve to pull out the magnetic tape 3 from the tape cassette and press it against the rotary head 5, and at the same time, the magnetic tape 3 is pressed against the heads 7, 12, and 13. There is. Further, the magnetic tape 3 is slidably contacted with the post 14 provided on the side of the voice control head 13, and the post 14 improves the running stability of the magnetic tape 3.

Next, FIG. 8 is a perspective view showing a conventional magnetic head device. As shown in FIG. 8, in the conventional magnetic head device, tape guides 18 are provided at both ends of a magnetic head 17 including a voice erasing head 12 and a voice control head 13 in the running direction of the magnetic tape 3. The tape guide 18 is for improving the stability of the running system of the magnetic tape 3 and improving the magnetic recording characteristics. The pair of restriction surfaces 19 of the tape guide 18 restrict the movement of the magnetic tape 3 in the width direction, and the sliding of the magnetic tape 3 on the sliding contact surface 20 of the tape guide 18 is stabilized.

[0009]

[Problems to be solved by the device]

 However, the above magnetic head device has the following problems. That is, if the thickness of the tape guide is small as shown in FIG. 9, the magnetic head device can be downsized, but the widthwise end of the magnetic tape can be held down by a small area due to the regulation surface of the tape guide. Become. In other words, a strong force is concentrated on the portion of the magnetic tape which comes into contact with the regulation surface of the tape guide, and the widthwise end of the magnetic tape is easily broken. Therefore, there is a problem in that the widthwise end of the magnetic tape is damaged and the magnetic characteristics of the magnetic tape are deteriorated. Further, when the thickness of the tape guide is large as shown in FIG. 10, the widthwise end of the magnetic tape is held by a relatively large area by the restriction surface of the tape guide, so the force applied to the magnetic tape is relatively weak, and the magnetic tape is relatively weak. Although the widthwise end of the magnetic tape is hard to break, the force applied to the magnetic tape reaches the central part of the magnetic tape, and wrinkles are easily generated in the central part of the magnetic tape. Therefore, there is a problem that the magnetic recording characteristics are deteriorated due to a spacing loss between the sliding surface of the magnetic head and the recording / reproducing surface of the magnetic tape. Further, there is a problem that it is not possible to cope with miniaturization of the magnetic head device.

An object of the present invention is to provide a magnetic head device having a tape guide in which the widthwise end of the magnetic tape is not bent and wrinkles are not generated in the center of the magnetic tape.

[0011]

[Means for Solving the Problems]

 The magnetic head device according to the present invention is a magnetic head device in which tape guides for guiding the magnetic tape are provided at both ends of the magnetic head in the magnetic tape running direction, and the tape guide is slidably contacted with a magnetic recording surface of the magnetic tape. A contact surface and a pair of guide portions projecting from the sliding contact surface to guide both ends in the width direction of the magnetic tape, and the protrusion portions are formed so as to face each of the pair of guide portions. A groove is formed between the protruding portion and the sliding contact surface so as to sandwich the widthwise end portion of the magnetic tape.

[0012]

[Action]

 According to the magnetic head device of the present invention, a protrusion is formed so as to face each of a pair of guides protruding from the sliding contact surface of the tape guide, and a magnetic field is formed between the protrusion and the sliding contact surface. Since the groove is formed so as to sandwich the widthwise end of the tape, the widthwise end of the magnetic tape can be guided so as to be sandwiched between the protrusion and the sliding contact surface. Therefore, it is possible to prevent the widthwise end portion of the tape from being broken and the center portion of the magnetic tape from being wrinkled. In addition, back tension can be applied to the magnetic tape by pressing the back surface of the magnetic tape which is slidably contacted with the front surface of the magnetic head with both projecting portions. Therefore, the magnetic tape can be pressed against the front surface of the magnetic head with an appropriate force during recording, reproducing or erasing.

[0013]

1 is a perspective view showing an embodiment of the magnetic head device of the present invention, and FIG. 2 is a front view showing a tape guide of the magnetic head device of the present invention. The same parts and components as those of the conventional example are designated by the same reference numerals.

In the magnetic head device of the present invention, tape guides 21 are provided at both ends of the magnetic head 3 including the voice erasing head 12 and the voice control head 13 in the running direction of the magnetic tape 3. The tape guide 21 serves to enhance the stability of the running system of the magnetic tape 3 and to improve the magnetic recording characteristics. A pair of tape guides 21 for restricting the sliding contact surface 23 and the movement of the magnetic tape 3 in the width direction are provided. It has a guide portion 25. The pair of guide portions 25 of the tape guide 21 are provided with protrusions 22 so as to face each other, and the shortest distance between the protrusions 22 is smaller than the width dimension of the magnetic tape 3. A slit-shaped groove 24 is formed between the protruding portion 22 of the tape guide 21 and the sliding contact surface 23 so as to sandwich the widthwise end portion of the magnetic tape 3.

3 and 4 are front views showing another embodiment of the tape guide of the present invention. In FIG. 3, the upper portion of the protruding portion 22 of the guide portion 25 of the tape guide 21 is curved. In FIG. 4, the upper side and the lower side of the protruding portion 22 of the guide portion 25 of the tape guide 21 are curved. This is to prevent the magnetic tape 3 from being damaged at the time of contact, as will be described later, because the tip of the protrusion 22 contacts the magnetic tape 3. The tape guide 21 may be made of metal, resin, or ceramic.

The size of the protruding portion 22 of the guide portion 25 is set to a value that allows the magnetic tape 3 that is pulled out from the tape cassette and pressed against the magnetic head 17 at the time of loading to get over the tip of the protruding portion 22. It That is, when both widthwise end portions of the magnetic tape 3 which have moved toward the magnetic head 17 at the time of loading hit the tip end portions of the protrusions 22, the widthwise end portions of the magnetic tape 3 are bent. , A value that allows the magnetic tape 3 to move to the front surface of the magnetic head 17 over the tip of the protruding portion 22, and when the magnetic tape 3 separates from the magnetic head 17, these protruding portions 22 are opposite to those described above. It is set to a value that can overcome the direction.

The position where the groove 24 is formed is on the rear side of the front end of the voice erasing head 12 and the voice control head 13, and moves as described above to press the magnetic tape 3 against the front face of the magnetic head 17. Can be supported at the groove 24, and a back tension can be applied to the magnetic tape 3 by the protrusion 22.

Next, the operation of the magnetic head device having the tape guide as described above will be described with reference to the embodiment shown in FIG. FIG. 5 is a diagram showing the flow until the magnetic tape comes into close contact with the magnetic head in the embodiment of FIG.

In the loading mechanism shown in FIG. 7, the loading pins 9 and 10 pull out the magnetic tape 3 from the tape cassette and wind the magnetic tape 3 around the rotary head 5 for about half a turn and press it. At this time, the magnetic tape 3 is also approached and pressed against the magnetic head 17.

When the magnetic tape 3 approaches the magnetic head device as shown by the chain double-dashed line in FIG. 5A, both ends of the magnetic tape 3 in the width direction of the magnetic tape 3 come into contact with the magnetic head 3 before contacting the magnetic head 17. It abuts the protrusion 22.

Here, since the loading pins 9 and 10 try to pull out the magnetic tape 3 to a predetermined position regardless of the contact of the guide portion 25 with the protruding portion 22, the force causes the magnetic tape 3 to move in the width direction of the magnetic tape 3. Both ends are deformed from the state shown in FIG. 5 (b) as shown in FIG. 5 (c), pass between the respective tip portions of the protrusions 22 and are pressed against the front surface of the magnetic head 17.

Next, as shown in FIG. 5D, the magnetic tape 3 which has been deformed and passed between the respective tip portions of the projecting portions 22 is subjected to tension on the magnetic tape 3, and this tension causes the magnetic tape 3 to move. Since the force to extend to 3 itself acts as shown by the arrow in FIG. 5 (d), this force moves to the groove 24 in the state shown in FIG. 5 (e) and pushes it against the front surface of the magnetic head 17. Applied.

When the magnetic tape 3 is in contact with the front surface of the magnetic head 17, back tension is applied to the magnetic tape 3 by the groove 24 as shown in FIG. 5A. The magnetic head 17 is pressed against the front surface of the magnetic head 17 to be in close contact therewith.

In this case, the protrusions 22 or grooves 24 act as guide poles and ensure an optimum magnetic tape angle. The guarantee of the optimum magnetic tape angle is given to the magnetic head 17 by the loading mechanism of each magnetic recording device because the loading mechanism of the magnetic recording device provided with the magnetic head 17 has a design dimension difference or variation. Even if there is a difference in the wrapping angle, if the position of the groove 24 according to the present invention is fixed, a constant wrapping angle can be maintained by any loading mechanism device. Therefore, the running property of the magnetic tape 3 is stabilized, the efficiency of magnetic recording characteristics is improved, and stable signal recording and reproduction or erasing can be performed.

FIG. 6 is an enlarged front view of the vicinity of the groove in FIG. As shown in FIG. 6, when the magnetic tape 3 is pressed against the front surface of the magnetic head 17, the control surface 26 of the tape guide 21 comes into contact with the widthwise end edges of the magnetic tape 3 to perform this positioning. Become. Therefore, since the magnetic tape 3 is in sliding contact with the magnetic gap of the magnetic head 17 at a regular angle, azimuth loss can be eliminated.

Further, as shown in FIG. 6, both ends in the width direction of the magnetic tape 3 are sandwiched by the protruding portion 22 and the sliding contact portion 23 of the tape guide 21, so that both ends in the width direction of the magnetic tape 3 are bent. Therefore, wrinkles do not occur in the central portion of the magnetic tape 3. Therefore, the widthwise ends of the magnetic tape 3 are damaged, and spacing loss occurs between the sliding surface of the magnetic head 17 and the recording surface of the magnetic tape 3, which deteriorates the magnetic recording characteristics. It can be prevented. Further, the dimension of the tape guide in the thickness direction can be shortened, and the magnetic head device can be miniaturized.

In the above-described embodiment, the tape guides 21 are provided at both ends of the magnetic head 17 including the voice erasing head 12 and the voice control head 13 in the sliding direction of the magnetic tape 3. It may be integrally molded with the magnetic head 17. Further, the tape guide 21 may be attached to the attachment base or the attachment frame for attaching the magnetic head 17, or may be integrally molded.

Further, the tape guide 21 and the magnetic head 17 may be formed as separate bodies instead of being integrated with each other. At this time, if the magnetic head 17 is independently fixed to the chassis or frame of the magnetic recording apparatus in which the magnetic head 17 is provided, and the tape guide 21 is arranged so as to sandwich the magnetic head 17 from both ends in the sliding direction of the magnetic tape 3. Of course, in that case, the tape guide 21 may be integrally provided with an appropriate supporting plate or the like, if necessary.

Further, in the above-described embodiment, the example in which the present invention is applied to the magnetic head device for the video tape recorder has been described. However, the audio cassette having a structure in which the magnetic tape is attached to and detached from the magnetic head device to slide. The present invention can be widely applied to tape recorders and other magnetic head devices of general magnetic recording devices in which a magnetic tape is detached and slid.

[0030]

【effect】

 According to the magnetic head device of the present invention, a protrusion is formed so as to face each of a pair of guides protruding from the sliding contact surface of the tape guide, and a magnetic field is formed between the protrusion and the sliding contact surface. Since the groove is formed so as to sandwich the widthwise end of the tape, the widthwise end of the magnetic tape can be guided so as to be sandwiched between the protrusion and the sliding contact surface. Therefore, the widthwise end of the tape is not broken, and wrinkles do not occur at the center of the magnetic tape. Therefore, it is possible to prevent the electromagnetic conversion characteristics from deteriorating due to the widthwise end of the magnetic tape being damaged or a spacing loss occurring between the sliding surface of the magnetic head and the recording surface of the magnetic tape. You can Also, the back tension of the magnetic tape can be applied by pressing the back surface of the magnetic tape which is slidably contacted with the front surface of the magnetic head with both protruding portions. Therefore, the magnetic tape can be pressed against the front surface of the magnetic head with an appropriate force during recording and reproduction, and the magnetic recording characteristics can be improved. Furthermore, the size of the tape guide in the thickness direction can be shortened, and the magnetic head device can be made smaller.

[Brief description of drawings]

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

FIG. 2 is a front view showing an embodiment of a tape guide of the magnetic head device shown in FIG.

FIG. 3 is a front view showing another embodiment of the tape guide.

FIG. 4 is a front view showing another embodiment of the tape guide.

5A and 5B are views showing a flow until the magnetic tape comes into close contact with the magnetic head in the embodiment of FIG. 3, in which FIG. 5A is a partially sectional plan view, and FIGS. Figure

FIG. 6 is an enlarged front view of the vicinity of the groove in FIG.

FIG. 7 is a diagram showing a magnetic tape loading mechanism used in one type of home video tape recorder (VTR).

FIG. 8 is a perspective view showing a conventional magnetic head device.

FIG. 9 is a perspective view showing a conventional tape guide.

FIG. 10 is a perspective view showing a conventional tape guide.

[Explanation of symbols]

 17 magnetic head 21 tape guide 22 protruding portion 23 sliding contact surface 24 groove 25 guide portion

Claims (1)

[Scope of utility model registration request] 1. A magnetic head device having tape guides for guiding a magnetic tape provided at both ends of the magnetic head in a magnetic tape running direction, wherein the tape guide is in sliding contact with a magnetic recording surface of the magnetic tape. A pair of guide portions projecting from the sliding contact surface and respectively guiding both ends in the width direction of the magnetic tape, and projecting portions are formed so as to face each of the pair of guide portions. A magnetic head device, wherein a groove is formed so as to sandwich the widthwise end of the magnetic tape between the magnetic head device and the contact surface.