JPH10282195A - Sensor element and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor element which has components of less component item, is inexpensive, compact, highly reliable and superior in electric characteristics. SOLUTION: A magneto-resistance element 7, a wiring board 11 and a magnet 14 are accommodated together with a supporting body 15 inside a metallic cover 22. The metallic cover 22 is formed of a non-magnetic metallic material having abrasion resistance. An earth terminal 23 is extended from the metallic cover 22, and the metallic cover 22 and the earth terminal 23 are set integrally. The earth terminal 23 has a solder-adhesive metallic film 24 of solderable solder, tin, nickel or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sensor element, for example, a sensor element such as a magnetic sensor used for a magnetic identification sensor for reading a magnetic pattern or magnetic information.

[0002]

2. Description of the Related Art An example of a conventional sensor element of this type is shown in FIG.
Shown in In the sensor element 1, magnetoresistive element patterns 5a and 5b made of a semiconductor material such as conductive films 4a and 4b and InSb are formed in a resin layer 3 formed on a magnetic substrate 2 in a zigzag or meandering manner. A chip-shaped magnetoresistive element 7 in which the conductive films 4a and 4b and the magnetoresistive element patterns 5a and 5b are covered with a protective film 6 is provided. The conductive films 4a and 4b have their end surfaces exposed from the protective film 6 and are electrically connected to external connection electrodes 8 and 9 formed on both end surfaces of the magnetoresistive element 7, respectively.

The magnetoresistive element 7 is arranged on a wiring board 11, and external connection electrodes 8 and 9 are connected to a circuit pattern 12 of the wiring board 11 by solder 13. Wiring board 11
Below, one magnetic pole (in FIG. 9, N
The magnets 14 are arranged with their poles facing each other, and a predetermined magnetic bias is applied to the magnetoresistive element 7. The magnet 14 has a recess 15 a formed in a support body 15 made of an insulating resin material.
Is fitted inside. The magnetoresistive element 7, the wiring board 11 and the magnet 14 are housed in a metal cover 16 together with the support 15. The magnetoresistive element 7 is electrically connected to an external circuit via a lead terminal 17 soldered to the circuit pattern 12 of the wiring board 11 with solder 13.

The metal cover 16 prevents a mechanical shock from being directly applied to the magnetoresistive element 7 when an object to be detected passes over the magnetoresistive element 7, and a weak output from the magnetoresistive element 7. Protects the output signal from external electromagnetic noise. Therefore, the metal cover 16 is provided with the metal cover 16.
A ground terminal 18 for discharging the charged electric charge is provided. Conventionally, the material most suitable for the characteristics required for each of the metal cover 16 and the ground terminal 18 has been independently adopted. Therefore, the ground terminal 18 is manufactured independently of the metal cover 16 and then attached to the metal cover 16 by the caulking 19.

[0005]

However, when the ground terminal 18 is manufactured as a part separate from the metal cover 16 and attached to the metal cover 16 by caulking 19, the following (1) to (4) are obtained. There was a problem, and the effect of manufacturing the metal cover 16 and the ground terminal 18 from suitable materials was not recognized, and conversely, the defect was conspicuous.

(1) Since the ground terminal 18 needs to be manufactured as a separate part from the metal cover 16, not only the number of parts is increased, but also the ground terminal 18 is connected to the metal cover 1.
Also, a process for mounting the sensor element 6 is required, and the cost of the sensor element 1 increases. (2) The grounding terminal 18 is caulked 19 and the metal cover 1
6, the metal cover 16 and the ground terminal 1
8, a contact resistance is generated, and the ground terminal 18
The effect is reduced even if a material having good conductivity is easily attached to solder. (3) The bonding strength between the ground terminal 18 and the metal cover 16 is weak. (4) The size of the mounting portion of the ground terminal 18 to the metal cover 16 is increased, such as the head of the caulking 19 protruding from the metal cover 16.

It is an object of the present invention to provide a highly reliable sensor element having a small number of parts, being inexpensive and compact, and having excellent electrical characteristics.

[0008]

In order to achieve the above object, a sensor element according to the present invention has a ground terminal electrically connected to a metal cover for covering an element body for detecting an object to be detected. It is characterized by being formed integrally with the metal cover.

With the above configuration, the ground terminal and the metal cover are formed integrally and are made of the same metal material. Therefore, the contact resistance between the ground terminal and the metal cover, which is generated in the conventional sensor element, is eliminated.

Further, in the sensor element according to the present invention, the metal cover is made of a wear-resistant metal material such as stainless steel, molybdenum, tungsten, titanium, etc. A conductive metal film is provided. Since the metal cover is made of a wear-resistant metal material, it is resistant to abrasion due to friction between the metal cover and the object. On the other hand, since the surface of the ground terminal is covered with a solder-adherable metal film that can be soldered, it can be easily soldered to a ground pattern provided on a printed wiring board or the like.

In the sensor element according to the present invention, the metal cover is made of a metal material which can be soldered, and a wear-resistant metal film made of a wear-resistant metal material is formed on the surface of the metal cover except for the ground terminal. It is characterized by being provided.
With the above configuration, the wear-resistant metal film protects the metal cover made of a solderable material from abrasion due to friction between the metal cover and the object.

Further, the sensor element according to the present invention is characterized in that a wear-resistant metal film is provided on the surface of the metal cover, and a solder-adherable metal film capable of being soldered is provided on the surface of the ground terminal. Features. With the above configuration,
The wear-resistant metal film protects the metal cover from abrasion due to friction between the metal cover and the object. On the other hand, the solder-adhesive metal film allows the ground terminal to be easily soldered to a ground pattern provided on a printed wiring board or the like.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a sensor element according to the present invention will be described with reference to the accompanying drawings.

[First Embodiment, FIGS. 1 to 4] The sensor element 21 shown in FIGS. 1 and 2 is obtained by applying the present invention to the sensor element 1 described in FIG. Houses the magnetoresistive element 7, the wiring board 11, the magnet 14, and the support 15. In FIG. 1, the portions corresponding to those in FIG. 9 are denoted by the corresponding reference numerals, and redundant description will be omitted.

The metal cover 22 is made of a wear-resistant non-magnetic metal material such as non-magnetic stainless steel. A ground terminal 23 extends from the metal cover 22, and the metal cover 22 and the ground terminal 23 are provided integrally. On the ground terminal 23, a solder-adhesive metal film 24 made of a solderable metal material such as solder (tin-zinc alloy), tin (Sn) or nickel (Ni) is formed.

The metal cover 22 can be manufactured, for example, as shown in FIGS. As shown in FIG. 3, a solder-adhesive metal film 24 is formed on a part of a metal plate 31 made of a non-magnetic metal material by a plating method. Next, as shown by a solid line in FIG.
Is punched in such a state that the metal cover 22 is unfolded so that the portion corresponding to is located at the position where the solder adhering metal film 24 is formed. The punched product is bent along the dotted line in FIG. 4 and then brazed or welded by abutting adjacent sides to each other. Thereby, the ground terminal 23 is
In addition to being formed integrally with the metal cover 22, a solder-adhesive metal film 24 is formed on the surface thereof.

In this way, the ground terminal 23 is formed at the same time when the metal cover 22 is manufactured, and there is no need to prepare the ground terminal 23 as an independent component. Then, not only is the step of attaching the ground terminal 23 to the metal cover 22 unnecessary, but also the mechanical bonding strength of the ground terminal 23 to the metal cover 22 is improved. Further, since the ground terminal 23 is formed integrally with the metal cover 22, contact resistance between the ground terminal 23 and the metal cover 22 can be eliminated.

[Second Embodiment, FIGS. 5 and 6] The sensor element 21a shown in FIG. 5 is different from the sensor element 21 shown in FIG. 1 in that the metal cover 22a is made of a non-magnetic material such as brass and soldered. A hard chromium plating film (abrasion-resistant metal film) 41 is formed on the surface of the metal plate except for a ground terminal 23a.

The metal cover 22a can be manufactured, for example, as shown in FIG. A hard chromium plating film 41 is formed on a metal plate 31a made of a non-magnetic metal material except for a part thereof. Next, as shown in FIG. 6, the metal cover 22a is punched out by punching so that a portion corresponding to the ground terminal 23a is set at a position where the hard chromium plating film 41 is not formed. .
After the punched product is bent along the dotted line in FIG. 6 and then brazed or welded with the adjacent sides abutting each other, the metal cover 22a of the sensor element 21a shown in FIG. 5 can be obtained.

In the sensor element 21a of FIG. 5, the hard chromium plating film 41 is not formed on the ground terminal 23a, and the ground terminal 23a is integrated with the metal cover 22a made of a solderable metal material. Since it is formed, the ground terminal 23a can be easily soldered to a ground pattern provided on a printed wiring board or the like.

[Third Embodiment, FIGS. 7 and 8] In the sensor element 21b shown in FIG. 7, the metal cover 22b is covered with a hard chromium plating film (abrasion-resistant metal film) 41 in the sensor element 21 of FIG. In addition, the ground terminal 23b is covered with a solderable metal film 24 that can be soldered. This metal cover 22b can be manufactured as follows.

As shown in FIG. 8, a metal plate 31b made of a non-magnetic metal material is subjected to primary plating to form a hard chromium plating film 41 entirely. Next, the portion of the metal plate 31b where the ground terminal 23b is to be formed is subjected to secondary plating, and a solder-adhesive metal film 24 such as solder, tin (Sn) or nickel (Ni) is formed on this portion. Next, a grounding terminal 2 is formed by punching at a position where the solder-adherent metal film 24 is formed.
3b so that a portion corresponding to 3b is set.
2b is punched out in a developed state. The punched product is
After being bent along the dotted line in FIG. 8, the adjacent sides are butted to each other and brazed or welded to obtain the metal cover 22b of the sensor element 21b in FIG.

The sensor element 21b shown in FIG.
3b, a solder-adhesive metal film 24 is formed by secondary plating.
Is formed, the ground terminal 23b can be easily soldered to a ground pattern provided on a printed wiring board or the like. In the third embodiment, the metal plate 3
The solder-adhesive metal film 24 may be formed on the entire surface 1b, and then the wear-resistant metal film 41 may be formed on the entire surface except for a portion corresponding to the ground terminal 23b. In this case, the metal plate 31b is punched and bent so that a portion corresponding to the ground terminal 23b is set at a position where the solder-adhesive metal film 24 is exposed.

[Other Embodiments] The sensor element according to the present invention is not limited to the above embodiment, and can be variously modified within the scope of the gist. For example, in the above-described embodiment, a magnetic sensor has been described as an example of a sensor element, but the present invention can be applied to, for example, a Hall element.
The metal covers 22, 22a, and 22b can be manufactured by press working, electric discharge machining, or the like instead of bending. The material of the metal cover 22 is molybdenum, tungsten, titanium, or the like in addition to stainless steel. There may be.

[0025]

As is apparent from the above description, according to the present invention, since the ground terminal is formed integrally with the metal cover, the distance between the ground terminal and the metal cover, which is generated in the conventional sensor element, is eliminated. Contact resistance is eliminated. Therefore, the resistance of the path of the current flowing from the metal cover to the ground terminal is always constant and can be a stable and low value. In addition, the ground terminal is formed simultaneously with the manufacture of the metal cover, and it is not necessary to prepare the ground terminal as an independent component, so that the number of parts is reduced, and a process for attaching the ground terminal to the metal cover is unnecessary. Also, the mechanical joining strength of the ground terminal to the metal cover can be increased.

Further, by providing a solder-adhered metal film on the surface of the ground terminal integrally formed with the metal cover made of a wear-resistant metal material, the metal cover is made of the wear-resistant metal material, so that the object to be detected can be removed. Strong against abrasion due to friction between On the other hand, since the surface of the ground terminal is covered with a solder-adherable metal film that can be soldered, it can be easily soldered to a ground pattern provided on a printed wiring board or the like.

Further, if the metal cover is formed of a solderable metal material and a wear-resistant metal film is provided on the surface of the metal cover while leaving the ground terminal, the ground terminal can be soldered. Therefore, the ground terminal can be easily soldered, and the wear-resistant metal film can protect the metal cover from abrasion due to friction between the metal cover and the object.

Further, by providing a wear-resistant metal film on the surface of the metal cover and providing a solder-adhesive metal film on the surface of the ground terminal, the wear-resistant metal film can cover the metal cover regardless of the material of the metal cover. The solder-adhesive metal film protects against abrasion due to rubbing with the object to be detected, and the ground terminal can be easily soldered to a ground pattern provided on a printed wiring board or the like.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment of a sensor element according to the present invention.

FIG. 2 is a perspective view showing the appearance of the first embodiment of the sensor element according to the present invention.

FIG. 3 is an explanatory view showing a manufacturing procedure of the metal cover of the sensor element of FIG. 1;

FIG. 4 is an explanatory view showing a manufacturing procedure of the metal cover following FIG. 3;

FIG. 5 is a perspective view showing an appearance of a second embodiment of the sensor element according to the present invention.

FIG. 6 is an explanatory view showing a manufacturing procedure of the metal cover of the sensor element of FIG. 5;

FIG. 7 is a perspective view showing the appearance of a third embodiment of the sensor element according to the present invention.

FIG. 8 is an explanatory view showing a manufacturing procedure of the metal cover of the sensor element of FIG. 7;

FIG. 9 is a sectional view of a conventional sensor element.

[Explanation of symbols]

 7 ... Magnetoresistance element 21, 21a, 21b ... Sensor element 22, 22a, 22b ... Metal cover 23,23a, 23b ... Ground terminal 24 ... Solder-adhesive metal film 41 ... Hard chrome plating film (wear-resistant metal film)

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[Procedure amendment]

[Submission date] February 13, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: Sensor element and manufacturing method thereof

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor element, for example, a sensor element such as a magnetic sensor used for a magnetic discrimination sensor for reading a magnetic pattern or magnetic information, and the like.
It relates to a manufacturing method .

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a highly reliable sensor element having a small number of parts, being inexpensive and compact, and having excellent electrical characteristics, and a method for manufacturing the same.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

Further, the sensor element according to the present invention is characterized in that a wear-resistant metal film is provided on the surface of the metal cover, and a solder-adherable metal film capable of being soldered is provided on the surface of the ground terminal. Features. With the above configuration,
The wear-resistant metal film protects the metal cover from abrasion due to friction between the metal cover and the object. On the other hand, the solder-adhesive metal film allows the ground terminal to be easily soldered to a ground pattern provided on a printed wiring board or the like. Further, the sensor according to the present invention
The method of manufacturing the element is to attach solder to the specified surface of the metal plate
Process for forming conductive metal film by plating method and ground terminal
The corresponding part is located at the position where the solder-adhesive metal film is formed.
Punching the metal plate so that
Work to form a metal cover in an unfolded state integrated with the terminal
And covering the element body for detecting the detection target.
Bending the unfolded metal cover.
It is characterized by having. Here, the metal plate is, for example, non-magnetic
Made of metal material. By the above method, the ground terminal
Formed at the same time as the manufacture of the metal cover, as an independent part
It is not necessary to provide a ground terminal. And a
The process of attaching the terminal to the metal cover is no longer necessary.
As well as the ground terminal machine for the metal cover
The overall bonding strength is also improved. Also, make sure that the ground terminal is
Ground terminal and metal cover.
The contact resistance between them can be eliminated.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a sensor element and a sensor according to the present invention will be described.
An embodiment of the present invention and a manufacturing method thereof will be described with reference to the accompanying drawings.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

[Other Embodiments] Sensor Element According to the Present Invention
The manufacturing method is not limited to the above-described embodiment, and can be variously changed within the scope of the gist. For example, in the above-described embodiment, a magnetic sensor has been described as an example of a sensor element, but the present invention can be applied to, for example, a Hall element. The metal covers 22, 22a, 2
2b can be manufactured by press working, electric discharge working or the like instead of bending work. As a material of the metal cover 22, besides stainless steel, molybdenum, tungsten,
It may be titanium or the like.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

Further, by providing a wear-resistant metal film on the surface of the metal cover and providing a solder-adhesive metal film on the surface of the ground terminal, the wear-resistant metal film can cover the metal cover regardless of the material of the metal cover. The solder-adhesive metal film protects against abrasion due to rubbing with the object to be detected, and the ground terminal can be easily soldered to a ground pattern provided on a printed wiring board or the like. Also, solder on the specified surface of the metal plate.
Adhesive metal film formed by plating method, equivalent to ground terminal
To the position where the solder-adhesive metal film is formed.
Stamped out a metal plate and integrated with the ground terminal
After forming the unfolded metal cover, detect the detection target.
Folded metal cover to cover the element body
The metal end is manufactured by grinding
The child is formed at the same time as the production of the metal cover,
It is not necessary to provide a ground terminal as a product. Soshi
The process for attaching the ground terminal to the metal cover
Not only is it unnecessary, but also the ground end to the metal cover
The mechanical bonding strength of the child is also improved. Also, the ground terminal
Since it is formed integrally with the metal cover,
The contact resistance with the metal cover can be eliminated.

Claims (4)

[Claims] 1. A sensor element, wherein a ground terminal electrically connected to a metal cover covering an element body for detecting a detection target is formed integrally with the metal cover. 2. The method according to claim 1, wherein the metal cover is made of a wear-resistant metal material, and a surface of the ground terminal is provided with a solder-adhesive metal film made of a solderable metal material. 2. The sensor element according to 1. 3. The metal cover is made of a solderable metal material, and a wear-resistant metal film made of a wear-resistant metal material is provided on a surface of the metal cover except for the ground terminal. The sensor element according to claim 1, wherein: 4. The method according to claim 1, wherein a wear-resistant metal film is provided on a surface of the metal cover, and a solder-adhesive metal film capable of being soldered is provided on a surface of the ground terminal. The sensor element according to any one of the preceding claims.