JPH0348565B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head in which a head element is fixed within a shield case with a resin, and a method for manufacturing the same.

BACKGROUND TECHNOLOGY This type of magnetic head is constructed by attaching a head element 2 to a shield case 1 using a resin material 3 as shown in FIG.
The most common method is to form a magnetic head by molding.

Problems to be Solved by the Invention In the case of the conventional magnetic head shown in FIG.
Because the tape travels in the direction of the arrow while in contact, the friction or static electricity caused by this may cause the coating agent on the tape to adhere to the resin part and fly upwards as shown at 4', or the tape to the head as shown in Figure 2. It may cover the front of the Therefore tape 4
There was a problem in that the contact between the head and the head became unstable, resulting in poor recording, playback, and erasing effects.

The reason for such peeling of the magnetic tape coating agent 4' is that frictional heat is generated due to friction between the magnetic tape 4 and the molding resin 3, and this frictional heat softens the magnetic tape binder. It is thought that this makes the coating agent 4' easy to peel off.
It is also believed that the peeled coating agent 4' is attracted by static electricity generated by friction between the magnetic tape 4 and the resin agent 3.

Japanese Utility Model Publication No. 41-13793 describes the mixing of a lubricant (zinc powder, molybdenum dioxide) that provides lubricity to the magnetic tape into the molding resin in order to solve the above problems with the magnetic head. ing.

The present invention eliminates the use of a special molding resin as in the conventional example, by forming concave grooves on the magnetic tape contacting surface of the magnetic head.
It is an object of the present invention to provide a magnetic head that can significantly reduce the influence of adhesion of a coating agent 4' as shown in FIGS. 2 and 2, and a manufacturing method that can easily manufacture this magnetic head.

Furthermore, Japanese Patent Publication No. 46-21179 discloses that a part of the tape contacting surface of the magnetic core is removed in order to reduce head noise caused by cracks in the tape contacting surface of the magnetic core, targeting a magnetic head element. However, it describes how a tape guide made of a non-magnetic material is bonded to this cut out portion with an adhesive, and how a recessed portion for storing the profit of the adhesive is formed on the tape contacting surface. However, the concave portion of the magnetic head element described in this publicly known document is formed in advance in the magnetic core and is only used as a reservoir for the adhesive when bonding the tape guide. This invention is different from the present invention. Furthermore, Japanese Patent Application Laid-Open No. 48-80023 describes the formation of a groove in a head element for a rotary disk, but like the above-mentioned publicly known document, this groove is also for an adhesive material reservoir. This is different from the present invention in which grooves are formed on the tape contact surface including the front surface of the shield case.

Means for Solving the Problems In order to achieve the above object, the present invention provides an area in which a resin agent for fixing the head element is exposed in the contact surface of the magnetic tape and located on both sides of the head element. forming grooves extending across the entire width of the shield case in a direction perpendicular to the running direction of the magnetic tape, and making the exposed portion of the resin lower than the contact surface of the magnetic tape. It is characterized by:

Further, the manufacturing method of the present invention includes a step of fixing the head element with a resin agent in a shield case having a hole formed on the front surface, and
Of the portions of the magnetic tape contact surface formed by the resin exposed through the hole of the shield case and the head element located on both sides of the head element, the area including the area where the resin is exposed through the hole is covered with the magnetic tape. In the direction perpendicular to the running direction of the magnetic tape,
This method is characterized by comprising a step of forming a groove extending over the entire width of the shield case.

Function The present invention has the above-described structure, and since the groove is formed across the entire width of the shield case including the exposed portion of the molding resin, the magnetic tape and the exposed portion of the molding resin are The contact area between the magnetic tape and the molding resin is reduced, the generation of frictional heat and static electricity is reduced, and the peeling of the magnetic tape coating and the adhesion of the peeled coating are reduced. This eliminates unstable contact between the magnetic tape and the head element, allowing stable recording, playback, erasing, etc.

Furthermore, according to the manufacturing method of the present invention, the grooves that span the entire width of the shield case are formed after the magnetic head is manufactured in the normal manufacturing process, so it is easy to manufacture the magnetic head having the grooves. can.

Embodiment An embodiment of the present invention will be described below with reference to FIG. In FIG. 3, reference numeral 5 denotes a shield case, and a head element exposure hole is formed in the front surface of this shield case 5. The shield case 5 houses a head element 6 and head element protection plates 7 and 8 made of non-magnetic material that also serve as track regulating plates. It is then molded and fixed. The head element 6, the head element protection plate 7,
8. A part of the molding resin 9 is exposed in the head element exposure hole of the shield case 5. 1
0 and 11 are grooves formed with a grindstone or the like on the contact surface of the magnetic tape after the head element 6 is molded and fixed in the shield case 5 with a resin agent 9; extends to the entire width of the shield case 5. As shown in FIG. 3, the grooves 10 and 11 are formed at portions located on both sides of the head element 6, and include molding resin 9 exposed on the contact surfaces with the magnetic tape. Also, groove 1
The directions 0 and 11 are directions perpendicular to the running direction of the magnetic tape, as shown in FIG.

According to the above embodiment, the following effects can be obtained.

(1) Grooves 10 and 11 are formed on the contact surface with the magnetic tape, including the exposed resin part for the mold, and the exposed part of the resin is lower than the contact surface of the magnetic tape, so that the magnetic tape and the resin This reduces the contact area between the magnetic tape and the resin, making it difficult for the coating agent applied to the magnetic tape to peel off due to frictional heat generated by friction between the magnetic tape and the resin, static electricity, etc., and the coating agent peeled off from the magnetic tape. becomes difficult to adhere to molding resin, etc.
Unlike the conventional example, functional deterioration due to unstable contact between the magnetic tape and the head element 6 can be prevented.

(2) In order to form the grooves 10 and 11 over the entire width of the shield case 5, a case where a recess is formed partially on the magnetic tape contact surface (Japanese Utility Model Publication No. 18108/1983)
Compared to the groove 10, it is easier to cut the groove 10 with a grindstone etc.
11 can be formed.

(3) After manufacturing using the same manufacturing process as before, groove 1
Since it is only necessary to form 0 and 11, conventional manufacturing equipment can be used without changing.

(4) Since there are fewer contact areas between the molding resin and the magnetic tape, which have high frictional resistance, there is less noise caused by friction (tape squeal), and the vibration of the magnetic tape during running is reduced, reducing wow and flatness. Characteristics improve.

(5) The concave grooves formed on the tape contact surface, including the front surface of the shield case, make it possible to adjust the wrapping angle of the tape around the magnetic head, thereby reducing the waviness of the playback frequency characteristics due to the contour effect. can be removed.

(6) The grooves formed on the tape contact surface, including the front surface of the shield case, reduce the coefficient of dynamic friction between the magnetic head and the tape, thereby reducing frequency modulation noise caused by longitudinal vibration that occurs in the tape's traveling direction.

EFFECTS OF THE INVENTION As is clear from the above embodiments, the present invention provides a magnetic tape in the traveling direction of the magnetic tape in the portion of the shield case located on both sides of the head element, including the area where the resin for fixing the head element is exposed. A concave groove extending to the entire width of the shield case is formed in a direction perpendicular to the magnetic tape, and the exposed portion of the resin is lower than the contact surface of the magnetic tape.
The magnetic tape runs while contacting the magnetic head,
Even if the coating agent applied to the magnetic tape adheres to the resin agent due to frictional heat, static electricity, etc., it remains inside the groove, so it will not fly out or cover the front surface of the head element as in the conventional case. It has the advantage of almost no such occurrence and always exhibits good recording, playback, and erasing functions. Furthermore, according to the present invention, the grooves formed on the tape contact surface including the front surface of the shield case reduce the waviness of the playback frequency characteristics caused by the tape wrapping angle and the frequency modulation noise caused by longitudinal vibration in the tape traveling direction. can. Furthermore, according to the manufacturing method of the present invention, after manufacturing in the same manufacturing process as the conventional method, a concave groove is formed on the tape contact surface over the entire width of the shield case, so the formation of the groove is also very simple. It has the advantage of

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views of a conventional magnetic head.
FIG. 3 is a perspective view of one embodiment of the magnetic head of the present invention. 5... Shield case, 6... Head element,
7, 8...Head element protection plate, 9...Resin agent, 1
0,11...concave groove.

Claims (1)

[Scope of Claims] 1. A shield case having a hole formed in the front surface, and a head element fixed in the shield case with a resin agent and partially exposed from the hole, the front surface of the shield case, the head element The resin material exposed through the hole in the shield case and the head element form a magnetic tape contact surface, and the area where the resin material is exposed from the hole in the portion of the magnetic tape contact surface located on both sides of the head element is A magnetic head in which a concave groove extending to the entire width of the shield case is formed in a direction perpendicular to the running direction of the magnetic tape, and the exposed part of the resin is lower than the contact surface of the magnetic tape. 2. A step of fixing the head element with a resin material in a shield case with a hole formed on the front surface, and a magnetic tape contact formed between the front surface of the shield case, the resin material exposed through the hole of the shield case, and the head element. Among the portions of the surface located on both sides of the head element, including the area where the resin material is exposed from the hole, extend across the entire width of the shield case in a direction perpendicular to the running direction of the magnetic tape. A method for manufacturing a magnetic head, comprising the step of forming a groove.