JPH05258223A - Erase head device - Google Patents

Abstract

PURPOSE:To obtain a stable erase effect by surely bringing a magnetic tape into contact and slide without floating the magnetic tape from a magnetic core in an erase head in a tape recorder, etc. CONSTITUTION:The magnetic core 2 erasing a half width of the magnetic tape 1 is molded by inserting it into a holding body 3, and a recessed part 6 is provided such that a constant width from the magnetic core 2 does not come into slidable contact with the magnetic tape 1, and the contacting and sliding surface 7 which is projected to the magnetic tape side is provided at the outside. When the magnetic tape 1 comes into slidable contact with the contacting and sliding surface 7, the tape simultaneously comes into slidable contact with the whole surface of the magnetic core 2. Since the magnetic core 2 and the magnetic tape 1 come safely and surely into slidable contact without floating, erasure defect is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an erasing head device used in a tape recorder or the like.

[0002]

2. Description of the Related Art When a magnetic core is slidably contacted with a tape, the surface of the magnetic core which is in contact with the tape at the same time is formed on the same plane or a gap is formed between the magnetic core and the surface. It was customary. 4 and 5 show a conventional example, FIG. 4 is a plan view, and FIG. 5 is a side sectional view. Figure 5
According to the conventional example, the magnetic core 2 made of a magnet that erases the lower half of the entire width of the magnetic tape 1 is integrally fixed to the holding body 3 by insert molding, and is attached to the tape recorder main body using the attachment hole 4. Has been. The holder 3 is made of a resin material, and the dummy core portion 5 is integrally formed. The dummy core portion 5 is formed in a dimensional relationship in the direction away from the tape with respect to the extension line of the tape contact surface of the magnetic core 2. Therefore, as shown in the figure, there is a disadvantage that the tape is tilted within the range of the gaps that are separated and the tape floats in the lower part of the magnetic core 2.

Therefore, mass production has been carried out by methods such as strictly demanding the accuracy of the tape running system and controlling the step between the magnetic core and the dummy core to be extremely small.

[0004]

However, increasing the mechanical dimensional accuracy of the tape running system increases the cost burden, and it is necessary to minimize the step between the magnetic core and the dummy core. The productivity had to be significantly reduced due to frequent mold repairs, and mass production had to be carried out while always being concerned about erasing defects.

Therefore, an object of the present invention is to provide an inexpensive and reliable erase head device by a simple means in order to solve the above problems.

[0006]

In order to solve the above-mentioned problems, an erasing head device according to the present invention comprises a magnetic core for erasing a substantially half width of a magnetic tape having a constant width in a direction perpendicular to the running direction, and the magnetic core. A dummy core provided at a predetermined distance from the core, a part of the front surface of the dummy core is projected from the front surface of the dummy core, and the front surface of the dummy core is inclined in the magnetic core direction from the protruding surface. It is a thing.

[0007]

According to the present invention, since the projection-shaped sliding contact portion acts so as to prevent the magnetic tape from floating and running from the surface of the magnetic core, the erasing failure does not occur.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.
This will be described in detail with reference to FIG.

FIG. 1 is an external perspective view showing an embodiment of the erasing head device of the present invention. The magnetic tape 1 is in sliding contact with the arcuate surface of the magnetic core 2 made of a magnet, and is opposed to a position on the lower side of the magnetic tape 1 where almost half width is erased. The magnetic core 2 is insert-molded into the holder 3 and is attached to the tape recorder using the attachment hole 4.
Further, the holder 3 is formed with a dummy core portion 50 made of an integral resin, and the shape of the surface of the dummy core portion 50 facing the magnetic tape 1 is a great feature. First, a concave groove 6 is provided in a portion adjacent to the magnetic core 2, and the dummy core portion 50 is separated from the magnetic core 2 by a predetermined distance. The front surface of the dummy core portion 50, that is, the surface facing the magnetic tape 1 is a conical sliding contact portion 7 on the lower side,
It continues to the maximum protruding surface 8 at the upper end.

The maximum protruding surface 8 and the sliding contact portion 7 near the maximum protruding surface 8 are projected toward the magnetic tape 1 side with respect to the extension line of the arcuate surface of the magnetic core 2. At least 1/4 of the tape width of the magnetic tape 1 is more concave than the extension of the arcuate surface of the magnetic core 2. Therefore, as is apparent from FIG. 2, since the magnetic tape 1 is running in a state in which it is wound at a predetermined angle, it makes sliding contact with the sliding contact portion 7 above the conical surface as shown in FIG. It can be brought into sliding contact with the entire surface without floating.

[0011]

As described above, according to the present invention, various problems such as an increase in cost due to the pursuit of accuracy, frequent mold repairs, and anxiety caused by the risk of erasing failure, which cannot be solved by the conventional method, are brought about. Can all be solved. That is, in the present invention, by devising the shape of the front surface of the dummy core, the magnetic tape can be slidably brought into good contact with the magnetic core. Therefore, the magnetic tape and the magnetic core can be securely connected to each other without strictly pursuing the precision of the parts. It is a very desirable and desirable erasing head device that makes a good sliding contact condition on the entire surface. In addition, the side effects such as scratching of the tape and the occurrence of loosening of the tape were also obtained without any problem.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an embodiment of an erasing head device of the present invention.

FIG. 2 is a top view of the apparatus of the same embodiment.

FIG. 3 is a side sectional view of the apparatus of the embodiment.

FIG. 4 is a top view showing a conventional erasing head device.

FIG. 5 is a side sectional view of the conventional device.

[Explanation of symbols]

 1 magnetic tape 2 magnetic core 6 concave groove 7 sliding contact portion 8 maximum protruding surface 50 dummy core portion

Claims (1)

[Claims] 1. A magnetic core for erasing a substantially half width of a magnetic tape having a constant width in a direction perpendicular to a running direction, and a dummy core provided at a predetermined distance from the magnetic core, the front surface of the dummy core being provided. An erasing head device, characterized in that a part thereof is projected from the front surface of the dummy core and the front surface of the dummy core is inclined from the protruding surface toward the magnetic core.