JP2000258446A - Rotating speed sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotating speed sensor of low price by integratedly molding the opening part side of a case so as to be internally mounted, and integratedly molding a connector terminal in a base body with a connector part. SOLUTION: The opening part side of a bottomed cylindrical metallic case 31 storing a base body 26 therein, and blockaded by the base body 26 is integratedly molded with a connector part 32 made of resin so as to be internally mounted. In addition, because the resin connector part 32 is integratedly molded therein with the connector terminal 30 of the base body 26, it is unnecessary that a cover separately from the case is provided for sealing up the interior of a rotating speed sensor as before, and the vicinity of the contact part of the case and the cover is sealed up by sealing resin. Thus, it is eliminated that the number of parts becomes large and the assembling manhour increases as before, and hence the sensor is at low price.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation speed sensor for detecting a rotation speed by a change in magnetism.

[0002]

2. Description of the Related Art A conventional rotational speed sensor will be described below with reference to the drawings. FIG. 4 is a side sectional view of a conventional rotation speed sensor.

In FIG. 4, reference numeral 1 denotes a magnetoresistive element composed of a pair of InSb electrically connected in series. Reference numeral 2 denotes a pair of Si substrates, on one surface of which the magnetoresistive element 1 is provided. 3 is a magnet, and this magnet 3
Is fixed to the other surface of the Si substrate 2. Reference numeral 4 denotes a base made of resin. The base 4 has a base terminal 5 made of metal at one end and holds the magnet 3 at a lower portion. Further, the base terminal 5 is connected to the magnetoresistive element 1 via a film 1a. And are electrically connected. A flexible wiring board 6 made of a polyimide film is provided on a side surface of the base 4.
And a processing circuit 7 made of an electronic component is provided on the upper surface of the flexible wiring board 6. The processing circuit 7 is electrically connected to the base terminal 5 and converts an output signal of the magnetoresistive element 1 into a pulse signal. Further, a metal lead terminal 8 is provided at the other end of the base 4, and this lead terminal 8 has one end electrically connected to the processing circuit 7 and the other end protruding from above. Reference numeral 9 denotes a cylindrical resin case having a bottom. The case 9 accommodates the base 4 therein and projects the connector portion 1 from the outer surface to the outside.
0 is provided. A connector terminal 11 is provided integrally inside the connector portion 10 of the case 9, and the other end of the lead terminal 8 is electrically connected to the connector terminal 11. A lid 12 is made of resin. The lid 12 closes an opening of the case 9. Reference numeral 13 denotes a sealing resin, which seals the vicinity of the contact portion between the case 9 and the lid 12.

[0004] Next, a description will be given of a method of assembling the conventional rotational speed sensor configured as described above.

First, the Si substrate 2 and the magnetoresistive element 1 are fixed to the lower surface of the magnet 3.

Next, after a magnet 3 provided with a Si substrate 2 and a magnetoresistive element 1 is fixed to a lower portion of a base 4, the magnetoresistive element 1 and one end of a base terminal 5 are thermally welded via a film 1 a. Make an electrical connection.

Next, after a processing circuit 7 made of an electronic component is mounted on the flexible wiring board 6, the base terminal 5 is electrically connected to one end of the processing circuit 7 by soldering. The flexible wiring board 6 is fixed to the side surface of the base 4 so that the lead terminal 8 is electrically connected to the other end by soldering.

Next, the flexible wiring board 6 and the base terminal 5 are soldered together with the flexible wiring board 6.
And the lead terminals 8 are soldered.

Next, the magnet 3, the flexible wiring board 6
After the base 4 is housed in the case 9 from above the case 9, the lead terminals 8 of the base 4 and the connector terminals 11 of the case 9 are electrically connected by soldering.

[0010] Finally, the upper opening of the case 9 is
Then, the vicinity of the contact portion between the case 9 and the lid 12 is sealed with a sealing resin 13.

The operation of the conventional rotation speed sensor assembled as described above will now be described.

A gear (not shown) of the other vehicle is provided below the case 9 so as to be opposed thereto, and the magnet 3 is rotated by the rotation of the unevenness provided on the gear (not shown).
The magnetic flux density with respect to a pair of magnetoresistive elements 1 provided below the magnetic field changes, and the change in the magnetic flux density is output by the magnetoresistive element 1 via the base terminal 5 as a sine waveform output voltage. Then, the output voltage of the sine waveform is converted into an output voltage of a rectangular wave by the processing circuit 7, and the other computer (not shown) is connected to the connector terminal 11 via the lead terminal 8 of the base 4.
To detect the rotation speed.

[0013]

However, in the above-mentioned conventional configuration, the lid 12 is provided separately from the case 9 in order to seal the inside of the rotation speed sensor. It is necessary to seal the vicinity of the contact portion with the sealing resin 13, and as a result, the number of parts increases and the number of assembly steps increases, so that there is a problem that the cost of the rotation speed sensor increases.

An object of the present invention is to solve the above-mentioned conventional problems and to provide an inexpensive rotation speed sensor that does not increase the number of parts and the number of assembling steps. It is assumed that.

[0015]

In order to achieve the above object, a rotation speed sensor according to the present invention comprises a pair of substrates provided with a magnetoresistive element on one surface, and fixed to the other surface of the pair of substrates. A magnet, a processing circuit for converting an output signal of the magnetoresistive element into a pulse signal, and a base terminal having one end electrically connected to the processing circuit and the other end electrically connected to the magnetoresistive element. A resin-made base having a connector terminal electrically connected to the processing circuit and holding the magnet, and a bottomed cylinder accommodating the base therein and having an opening closed by the base A metal case, and a resin connector part integrally formed so as to house the opening side of the case, and a connector terminal in the base integrally formed inside. , This configuration According words, the number of components is increased, rather than that becomes many assembly steps, it is capable of providing an inexpensive speed sensor in cost.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a pair of substrates provided with a magnetoresistive element on one surface, a magnet fixed to the other surface of the pair of substrates, A processing circuit for converting an output signal of the magnetoresistive element into a pulse signal; a base terminal having one end electrically connected to the processing circuit and the other end electrically connected to the magnetoresistive element; A resin base having the connector terminals connected to each other and holding the magnet, and a bottomed cylindrical metal base having the base housed therein and having an opening closed by the base. This case is provided with a case, and a resin connector portion formed integrally with the case so as to house the opening side of the case and a connector terminal in the base integrally formed inside. The substrate inside In addition, the resin-made connector portion is integrally molded with the resin-made connector portion so as to house the opening side of a bottomed cylindrical metal case in which the opening portion is closed by the base, and the resin-made connector portion has Because the connector terminals on the base are integrally molded inside,
It is not necessary to provide a lid separately from the case in order to seal the inside of the rotation speed sensor as in the related art, and to seal the vicinity of the abutting portion between the case and the lid with a sealing resin. In addition, an inexpensive rotation speed sensor can be obtained.

According to a second aspect of the present invention, the melting point of the resin material in the connector portion of the first aspect is lower than the melting point of the resin material in the base. Is lower than the melting point of the resin material in the base, the resin material in the base is melted even when a temperature corresponding to the melting point of the resin material in the connector is applied to the base when the connector is formed. However, this has the effect that the rotation speed sensor can be easily assembled.

According to a third aspect of the present invention, there is provided the connector according to the first or second aspect, wherein polybutylene terephthalate (PBT) is used as the resin material, and polyphenylene sulfide (PBT) is used as the resin material in the base.
According to this configuration, polybutylene terephthalate (PBT) is used as the resin material in the connector portion, and as the resin material in the base,
Since polyphenylene sulfide (PPS) is used, the melting point of the resin material in the connector becomes lower than the melting point of the resin material in the base, and as a result, the resin material in the base is melted when the connector is molded. Therefore, the rotation speed sensor can be easily assembled.

According to a fourth aspect of the present invention, a pair of substrates having a magnetoresistive element provided on one surface, a magnet fixed to the other surface of the pair of substrates, and an output signal of the magnetoresistive element are provided. A processing circuit for converting to a pulse signal, a base terminal having one end electrically connected to the processing circuit and the other end electrically connected to the magnetoresistive element, and a connector terminal electrically connected to the processing circuit And a resin-made base holding the magnet, a cylindrical metal case having a bottom and containing the base therein and having an opening closed by the base; and an opening in the case. A resin connector part is formed integrally with the inside of the base part so as to house the inside, and a connector terminal of the base is integrally formed inside, and is provided on an outer surface of the connector part so as to protrude outward. Made of metal According to this configuration, since the metal mounting portion is provided on the outer surface of the connector portion so as to protrude outward, the mounting position of the metal mounting portion is changed. This has the effect that the mounting direction of the rotation speed sensor can be easily changed only by the above operation.

According to a fifth aspect of the present invention, the metal mounting portion of the fourth aspect is insert-molded during resin molding of the connector portion. According to this configuration, the metal mounting portion is formed. Is formed by insert molding at the time of resin molding of the connector portion, so that the mounting direction of the metal mounting portion can be freely changed and the mounting portion can be easily formed.

According to a sixth aspect of the present invention, there is provided a metal mounting portion according to the fifth aspect, wherein a metal case is provided with a case insertion hole into which the metal case is inserted. According to this configuration, a case insertion hole into which a metal case is inserted is provided in the metal mounting portion, and the case insertion hole is provided. Since there is a gap between the hole and the outer surface of the case through which the resin for molding the connector passes, the resin for molding the connector is provided over the entire outer surface of the case. ,
This has an effect that the fixing strength of the attachment portion to the case is sufficiently ensured.

Hereinafter, a rotation speed sensor according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side sectional view of a rotational speed sensor according to an embodiment of the present invention, and FIG. 2 is a side sectional view showing a state in which a magnetoresistive element and a substrate are fixed to a magnet in the rotational speed sensor.

1 and 2, reference numeral 21 denotes a magnetoresistive element made of a pair of InSb electrically connected in series. Reference numeral 22 denotes a pair of Si substrates, and the magnetoresistive element 21 is provided on the lower surface of the Si substrate 22. Reference numeral 23 denotes a film made of a polyimide resin. The film 23 is provided with a connection layer 24 made of a copper foil. The film 23 is fixed to the magnetoresistive element 21 via the connection layer 24. 24 is the magnetoresistive element 21
Is electrically connected to 25 is a magnet, and this magnet 25
The upper surface of the Si substrate 22 is fixed to the lower surface of the substrate. 26
Is a base made of resin. This base 26 has a base terminal 27 made of metal at the lower part and holds the magnet 25. A flexible wiring board 28 made of a polyimide film is provided on a side surface of the base 26, and a processing circuit 29 made of an electronic component is provided on an upper surface of the flexible wiring board 28. The processing circuit 29 has one end electrically connected to the base terminal 27 and converts an output signal of the magnetoresistive element 21 into a pulse signal. Further, a metal connector terminal 30 is provided on the upper portion of the base 26, and one end of the connector terminal 30 is electrically connected to the other end of the processing circuit 29.
Reference numeral 31 denotes a bottomed cylindrical metal case.
Has the base 26 housed inside, and the opening is closed by the base 26. Reference numeral 32 denotes a resin connector. The connector 32 is integrally formed so as to house the opening side of the case 31, and the connector 2
The connector terminal 30 of FIG. 6 is integrally formed inside, and a resin mounting portion 34 provided with a metal mounting bracket 34a so as to protrude outward from the outer surface is integrally formed.

In one embodiment of the present invention described above, the base 26 is housed inside, and
The connector part 3 made of resin so as to house the opening side of the bottomed cylindrical metal case 31 whose opening is closed by
2 and the connector terminal 32 of the base 26 is integrally formed inside the resin connector portion 32. Therefore, in order to seal the inside of the rotation speed sensor as in the related art, In addition to providing a lid separately from the case, it is not necessary to seal the vicinity of the abutting portion between the case and the lid with a sealing resin, thereby increasing the number of parts and the number of assembling steps as in the conventional case. Since the rotation speed sensor is not lost, the rotation speed sensor can be provided at a low cost.

Next, a method of assembling the rotational speed sensor according to the embodiment of the present invention configured as described above will be described.

First, InS is applied to the lower surfaces of the pair of Si substrates 22.
b is formed by vapor deposition.

Next, a polyphenylene sulfide (PP) melted by heating to about 270 ° C. in a mold (not shown)
After injecting S), the substrate is cooled to form the base 26.

Next, after the magnet 25 is fixed to the lower portion of the base 26, the Si substrate 22 to which the film 23 is fixed is fixed to the lower surface of the magnet 25.

Next, a processing circuit 2 made up of electronic parts is
9 so that one end of a flexible wiring board 28 having the surface 9 mounted thereon is electrically connected to the base terminal 27 of the base 26 and the other end is electrically connected to the connector terminal 30 of the base 26. A flexible wiring board 28 is mounted on the side surface of 26.

Next, the flexible wiring board 28 and the base terminal 27 are soldered, and the flexible wiring board 28 and the connector terminal 30 are soldered.

Next, after the base 26 provided with the magnet 25, the magnetoresistive element 21, and the processing circuit 29 is housed in the case 31, the upper opening of the case 31 is
Closed by the top of

Next, after setting one molding die (not shown) so as to be located above the other molding die (not shown), the one molding die (not shown) and Polybutylene terephthalate (PBT), which has been heated to about 240 ° C. and melted, is injected into the other molding die (not shown), and then cooled. It is molded integrally so as to be installed inside.

In this case, since polybutylene terephthalate (PBT) is used as the resin material in the connector portion 32 and polyphenylene sulfide (PPS) is used as the resin material in the base 26, the melting point of the resin material in the connector portion 32 is reduced. Is lower than the melting point of the resin material in the base 26, and as a result, the connector 3
Since the resin material in the base 26 is not melted when the molding 2 is formed, the rotation speed sensor can be easily assembled.

Next, the operation of the rotation speed sensor according to the embodiment of the present invention assembled as described above will be described.

A gear (not shown) of the other vehicle is provided below the case 31 so as to be opposed to each other. The rotation of the unevenness provided on this gear (not shown) causes the magnet 2 to rotate.
The magnetic flux density for a pair of magnetoresistive elements 21 provided below the magnetic resistance element 5 changes, and this change in magnetic flux density is
Output as a sine waveform output voltage via the base terminal 27. The output voltage of the sine waveform is processed by the processing circuit 29.
The output voltage is converted into a rectangular wave output voltage and output to the other computer (not shown) through the connector terminal 30 of the base 26 to detect the rotation speed.

In the rotation speed sensor according to one embodiment of the present invention, a configuration has been described in which the resin mounting portion 34 is integrally provided so as to protrude outward from the outer surface of the connector portion 32. As shown in FIG. 3, a metal mounting portion 41 may be provided on the outer surface of the connector portion 32 by insert molding so as to protrude outward. Since the metal mounting portion 41 is provided on the side surface so as to protrude outward, the mounting direction of the rotation speed sensor can be easily changed only by changing the mounting position of the metal mounting portion 41. It has a function and effect.

Since the metal mounting portion 41 is insert-molded at the time of resin molding of the connector portion 32, the mounting direction of the metal mounting portion 41 can be freely changed, and the mounting portion 41 can be formed. It has the effect of being easily performed.

Further, the metal mounting portion 41 is provided with a case insertion hole 42 into which the metal case 31 is inserted, and the connector portion 32 is provided between the case insertion hole 42 and the outer surface of the case 31. Since the clearance 43 through which the resin for molding passes is provided, the resin for molding the connector portion 32 is provided over the entire circumference of the outer surface of the case 31.
1 has a function and an effect that a sufficient fixing strength to 1 is secured.

[0040]

As described above, the rotation speed sensor of the present invention is
A pair of substrates provided with a magnetoresistive element on one surface, a magnet fixed to the other surface of the pair of substrates, a processing circuit for converting an output signal of the magnetoresistive element into a pulse signal, and A resin having one end electrically connected and a base terminal electrically connected to the magnetoresistive element at the other end and a connector terminal electrically connected to the processing circuit, and holding the magnet. And a base made of a metal having a cylindrical shape with a closed bottom whose opening is closed by the base and an opening side of the case are integrally molded, And a resin connector portion formed integrally with the connector terminal of the base inside. According to this configuration,
The base is housed inside, and is integrally formed with a resin connector part so as to house the opening side of a bottomed cylindrical metal case whose opening is closed by the base. In the connector part, the connector terminal of the base is integrally formed inside, so that a lid is provided separately from the case to seal the inside of the rotation speed sensor as in the related art, and the case and the lid are It is no longer necessary to seal the vicinity of the contact portion with a sealing resin, thereby increasing the number of parts and the number of assembling steps as in the conventional case. This has the effect that a number sensor can be provided.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a rotation speed sensor according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing a state where a substrate and a magnetoresistive element are fixed to a magnet in the rotation speed sensor.

FIG. 3 is a side sectional view of a rotation speed sensor according to another embodiment of the present invention.

FIG. 4 is a side sectional view of a conventional rotation speed sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Magnetoresistive element 22 Substrate 25 Magnet 26 Substrate 27 Substrate terminal 29 Processing circuit 30 Connector terminal 31 Case 32 Connector part 34, 41 Mounting part 42 Case insertion hole 43 Gap

Continuing on the front page (72) Inventor Osamu Mitsumura 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Koji Nabeya 1006 Okadoma Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. ) 2F077 AA43 PP14 VV03 VV11 VV33 VV35 WW06

Claims (6)

[Claims] 1. A pair of substrates provided with a magnetoresistive element on one surface, a magnet fixed to the other surface of the pair of substrates, and a processing circuit for converting an output signal of the magnetoresistive element into a pulse signal. And a substrate terminal having one end electrically connected to the processing circuit and the other end electrically connected to the magnetoresistive element, and a connector terminal electrically connected to the processing circuit, and A resin-made base holding a magnet, a bottomed cylindrical metal case that houses the base therein and has an opening closed by the base;
Molded integrally so as to house the opening side of the case,
A rotational speed sensor comprising a resin connector portion formed integrally with the connector terminal of the base. 2. The rotation speed sensor according to claim 1, wherein the melting point of the resin material in the connector portion is lower than the melting point of the resin material in the base. 3. The rotation speed sensor according to claim 1, wherein polybutylene terephthalate (PBT) is used as a resin material in the connector portion, and polyphenylene sulfide (PPS) is used as a resin material in the base. 4. A pair of substrates provided with a magnetoresistive element on one surface, a magnet fixed to the other surface of the pair of substrates, and a processing circuit for converting an output signal of the magnetoresistive element into a pulse signal. And a substrate terminal having one end electrically connected to the processing circuit and the other end electrically connected to the magnetoresistive element, and a connector terminal electrically connected to the processing circuit, and A resin-made base holding a magnet, a bottomed cylindrical metal case that houses the base therein and has an opening closed by the base;
Molded integrally so as to house the opening side of the case,
A rotational speed including a resin connector portion formed integrally with a connector terminal in the base and a metal mounting portion provided on an outer surface of the connector portion so as to protrude outward; Sensor. 5. The rotation speed sensor according to claim 4, wherein the metal mounting portion is insert-molded during resin molding of the connector portion. 6. A case insertion hole in which a metal case is inserted into a metal attachment portion, and a resin for forming a connector portion passes between the case insertion hole and an outer surface of the case. The rotation speed sensor according to claim 5, wherein a gap is provided.