JP3487543B2 - Rotation sensor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation sensor for detecting a rotation speed of a wheel of an automobile or an output shaft of an engine.

[0002]

2. Description of the Related Art An example of a conventional rotation sensor of this type is shown in FIG. The pole body 1 and the magnet 2 are housed in a resin bobbin 3. The bobbin 3 is formed by injection molding. A coil winding portion 4 is provided on the outer surface of the bobbin 3. The coil winding portion 4 has a flange 6 that defines a position on one end side of the winding range of the coil 5 wound around it, that is, a position on the tip side of the pole body 1, and another flange 7 that defines a position on the other end side. It is provided by integral molding. The bobbin 3 and the coil 5 are covered with a resin outer layer portion (not shown) in a state where the tip of the pole body 1 is projected to the outside.
Further, during injection molding of the bobbin 3, the pole body 1 and the magnet 2 are fixed in position by a fixing pin (not shown) so as not to move by injection pressure, but a residual hole 8 is formed because the fixing pin is taken out after molding. . In this example, a pair of residual holes 8
Is occurring. As another conventional example, Japanese Patent Laid-Open No. 6-342.
002 publication etc. are mentioned.

[0003]

However, in the above conventional rotation sensor, the flange 6 of the bobbin 3 is
Since it is formed in a disk shape having a uniform thickness including the tip thereof, when the coil 5 is wound around the coil winding portion 4, the wire is caught at the corner of the tip 10 of the flange 6 and entangled. There was a problem that it was difficult to wind it uniformly. Since this winding process is usually automated, its entanglement becomes a serious problem. Further, in the conventional rotation sensor, since the flange 6 is formed in a disk shape having a uniform thickness as described above, it is easy to form a gap between the flange 6 and the outer layer portion coated on the outside thereof. Therefore, the water, salt water, etc. 9 that has penetrated along the boundary between the protruding portion of the pole body 1 and the outer layer portion passes through the gap between the flange 6 and the outer layer portion,
Further, there is a possibility that the tip of the flange 6 may be crossed and the coil 5 may be reached. That is, there is a problem that the coil 5 is rusted, corroded, or broken due to the intrusion of water, salt water or the like 9.

Since the open end 11 of the remaining hole 8 of the bobbin 3 also has a uniform thickness, a gap is likely to be formed between the open end 11 of the flange 6 and the outer layer portion, like the tip 10 of the flange 6.
Therefore, the water, salt water, etc. 12 that has penetrated along the boundary between the protruding portion of the pole body 1 and the outer layer portion passes through the gap between the outer surface of the pole body 1 and the bobbin 3, and further the remaining hole 8 of the bobbin 3. There is a risk of passing through the gap between the open end 11 and the outer layer to reach the terminal (not shown) of the coil 5.
That is, there is a problem that the coil 5 and terminals are rusted, corroded, or even broken due to the intrusion of water, salt water, or the like 9.
In FIG. 8, reference numeral 13 indicates a holder, and the holder 13 holds the pole body 1 and the magnet 2 before the injection molding of the bobbin 3.

An object of the present invention is to easily wind a coil without being entangled, and to sufficiently prevent intrusion of water, salt water, etc. from the outside, and to make them simple and simple. It is to provide a rotation sensor that can be easily realized. Another object of the present invention is to provide a rotation sensor that can sufficiently prevent water, salt water, etc. from entering the terminal side of the open end of the remaining hole of the bobbin.

[0006]

[Means for Solving the Problems]
Because, protruded a resin bobbin for accommodating the port Rubodi a magnet, a coil wound around the coil winding portion provided on the outer surface of the bobbin, the bobbin and coil the tip of the pole body to the outside In a rotation sensor including a resin outer layer portion that covers the coil winding state, a flange that defines one end side of a winding range of the coil is integrally formed in the coil winding portion at a position on the tip side of the pole body. The front end of the flange is formed into an inclined surface so that the coil side does not get entangled when the coil is wound, and is formed into a tapered shape by using the inclined surface.
It

As described above, since the tip of the flange defining one end of the coil winding range is formed on the inclined surface as described above, the wire rod is slightly displaced out of the range when the coil is wound. Even if it is rolled up, it will hit the inclined surface. Therefore, the wire naturally descends the inclined surface,
It will be wound in the correct winding position. Also, the tip of the pre-Symbol flange, which is formed on said as tapered, the better the close contact between the outer layer portion of the resin to be coated by conventional injection molding on the outside, whereby the water,
It is possible to prevent intrusion of salt water or the like. Moreover, since the tapered shape of the flange tip portion is formed by utilizing the inclined surface, it is possible to easily realize the two effects of preventing the entanglement and improving the adhesiveness with a single configuration.

The invention according to claim 1 of the present application is a bobbin made of resin for accommodating a pole body and a magnet, and a coil wound around a coil winding portion provided on an outer surface of the bobbin.
In a rotation sensor having a resin outer layer that covers the bobbin and the coil with the tip of the pole body protruding outward, the pole body and the magnet are not moved by injection pressure during injection molding of the bobbin. As described above, the tip end opening portion of the residual hole generated by taking out the fixing member for fixing the position is formed in a tapered shape. According to the present invention, since the tip end opening of the residual hole is formed in a taper shape, a close contact state with the resin outer layer part which is normally covered by injection molding on the outside thereof is improved, whereby water, It is possible to prevent intrusion of salt water or the like.

The invention according to claim 2 of the present application is a bobbin made of resin for accommodating a pole body and a magnet, a coil wound around a coil winding portion provided on an outer surface of the bobbin, the bobbin, and In a rotation sensor having a resin outer layer that covers a coil with the tip of the pole body protruding to the outside, the coil winding portion is a flange that defines one end side of a winding range of the coil. Is integrally formed at a position on the tip end side of the pole body, and the tip end portion of the flange is formed as an inclined surface so that the coil side does not get entangled when the coil is wound, and the inclined surface is utilized. A tip of a residual hole formed by taking out a fixing member that is formed in a tapered shape and fixes the pole body and the magnet so as not to move by injection pressure during injection molding of the bobbin. It is characterized in that the end opening is formed in a tapered shape.

According to the present invention, since the flange defining the one end of the coil winding range has the tip portion formed on the inclined surface as described above, the wire rod is positioned slightly outside the range when the coil is wound. Even if the tape is wound while being displaced, it will hit the inclined surface. Therefore, the wire naturally goes down the inclined surface and is wound in the correct winding position. Further, according to the present invention, since the tip end of the flange and the tip end opening of the residual hole are formed in a tapered shape as described above, an outer layer part made of a resin, which is usually covered by injection molding, is provided on the outer side thereof. Improves the close contact state with water, thereby preventing intrusion of water, salt water, and the like. Moreover, since the tapered shape of the flange tip portion is formed by using the inclined surface, the two effects of preventing the entanglement and improving the adhesiveness can be easily realized with a single configuration.

In the invention according to claim 3 of the present application, in the invention according to claim 1 or 2 , the tapered portion of the bobbin is fused with an outer layer located outside thereof. It is characterized by that. According to the present invention, since the flange tip of the bobbin and the tip opening of the residual hole and the outer layer are fused and integrated with each other,
The adhesion is in a state of being almost perfect, so that infiltration of water, salt water, etc. can be prevented more sufficiently. And
This fused state can be easily realized by utilizing the tapered shape because the tip end thereof is easily melted.

Further, in the invention according to claim 4 of the present application, in the invention according to any one of claims 1 to 3 , the tip end opening portion of the residual hole is formed on an inclined surface which descends in the tip direction of the pole body. It is characterized by that.
According to the present invention, it is possible to increase the leakage resistance of water, salt water, etc. to the terminal side by the inclined surface structure formed at the tip end opening portion of the residual hole, whereby the infiltration of water, salt water, etc. Can be more sufficiently prevented.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 is a front view of a bobbin portion of a rotation sensor according to an embodiment of the present invention, and FIG. 2 is a front view of FIG.
II-II line sectional view, FIG. 3 is a III-III line sectional view of FIG. 1, FIG.
[FIG. 3] is a front view showing a cross section of an outer layer portion of the rotation sensor according to the present embodiment. As shown in these drawings, in the rotation sensor of the present embodiment, a bobbin 3 accommodates a pole body 1 and a magnet 2, and the outer surface of the bobbin 3 is a coil whose range is defined by both flanges 6 and 7. A winding part 4 is provided. In addition, in the vicinity of the upper portion of the magnet 2, two remaining holes 8 are formed by taking out a fixing member (not shown) for fixing the position of the pole body 1 and the magnet 2 so as not to move by injection pressure during injection molding of the bobbin 3. Is left. The above structure is the same as the conventional structure shown in FIG.

The tip end of the flange 6 which defines one end side of the coil winding range of the coil winding portion 4 has the inclined surface 1 on the side facing the coil 5 (not shown in FIGS. 1 and 2).
4 is formed. The inclination direction of the inclined surface 14 is a direction in which the coil 5 is not caught and entangled during winding as illustrated. Further, the tip end of the flange 6 is formed on the inclined surface 1
4 is used to form a taper shape and has a tapered tip 15
Has become. In the present embodiment, as shown in the figure, it is formed in a taper shape having two tapered tips 15, but it may be formed of one or three or more. The other end of the flange 7 on the coil side is chamfered so that the wire of the coil is not entangled.

Furthermore, the tip end opening of the remaining hole 8 of the bobbin 3 is also formed in a tapered shape over the entire circumference to form a tapered tip 16. In the present embodiment, as shown in the figure, it is formed in a taper shape having two tapered tips 16, but it may be formed of one or three or more. The method of forming the tapered tips 15 and 16 can be performed by forming a mold (not shown) for injection molding into a corresponding shape.

As shown in FIG. 4, in the rotation sensor, cable wires 17 and 18 are electrically connected to the coil 5 through terminals 19 and 20, respectively. The bobbin 3 and the coil 5 are covered with a resin outer layer portion 21 formed by injection molding, as shown in the figure, with the tip of the pole body 1 protruding to the outside. In the present embodiment, the tapered tips 15 and 16 of the bobbin 3 and the outer layer portion 21.
And are fused to each other at their contact portions. The fusion of the two can be easily realized by a normal injection molding process of the outer layer portion 21 by using a material having a lower melting point than the material of the outer layer portion 21 for the material of the bobbin 3. That is, the tapered tip 1 is heated by the heat during the injection molding of the outer layer portion 21.
5 and 16 melt a little and solidify together with the outer layer portion 21 to be in a fused state. As an example of a specific combination of such materials, nylon 66 and bobbin 3 are used for the outer layer portion 21.
Examples include nylon 6. 5 shows the fused portion 22 in which the tapered tip 15 of the flange 6 is melted and fused to the outer layer portion 21, and FIG. 6 shows that the tapered tip 16 of the residual hole 8 is fused and the outer layer portion 2 is melted.
1 shows a fused portion 23 fused with 1.

Next, the operation of the rotation sensor according to the above embodiment will be described. According to the present embodiment, the coil 5
The flange 6, which defines one end of the winding range, has the tip end portion formed on the inclined surface 14 as described above, and therefore the wire rod is slightly displaced outside the winding range when the coil 5 is wound. Even if it is struck, it will hit the inclined surface 14. Therefore, the wire naturally descends from the inclined surface 14 and is wound in the correct winding position. Further, the tip of the flange 6 is formed in a tapered shape as described above, and the tapered tip 1 is formed.
Since 5 is formed, the state of close contact with the outer layer portion 21 made of resin, which is coated on the outer side, is improved, and water,
It is possible to prevent intrusion of salt water or the like. Moreover, the taper shape of the tip of the flange 6, that is, the tapered tip 15
Is formed by utilizing the inclined surface 14, so that it is possible to easily realize two effects, that is, the prevention of the entanglement of the coil wire material and the prevention of the intrusion of water, salt water, etc. by improving the adhesion, with a single configuration. You can

Furthermore, since the tip opening of the residual hole 8 is also formed in a taper shape and the tapered tip 16 is formed, the state of close contact with the outer layer portion 21 made of resin, which is covered on the outer side, is improved. , This part also has terminals 19, 2
It is possible to prevent water, salt water, etc. from entering the 0 side.

In addition, the taper-shaped tapered tips 15 and 16 of the bobbin 3 are fused and integrated with the outer layer 21 existing on the outside of the bobbin 3, respectively. Since the adhesiveness of 23 becomes almost perfect, it is possible to more sufficiently prevent intrusion of water, salt water, etc. from the outside. The fused state can be easily realized by utilizing the tapered shape because the tip end thereof is easily melted.

FIG. 7 is a vertical sectional view of a bobbin portion showing another embodiment of the present invention. In the present embodiment, the tip opening portion of the residual hole 8 is a tapered tapered tip 1
6 is formed, and is also formed on the inclined surface 24 that descends in the front end direction of the pole body 1. Since other configurations are the same as those of the above-described embodiment, the same parts are designated by the same reference numerals and the description thereof will be omitted. According to the present embodiment, the structure of the inclined surface 24 formed in the residual hole 8 and defined by the inclination can increase the water leakage resistance to the terminals 19 and 20 side. Infiltration can be prevented more sufficiently.

[0021]

According to the present invention, the coil can be easily wound without being entangled, and the intrusion of water, salt water, etc. from the outside can be sufficiently prevented. Can be easily realized in. That is,
The flange that defines one end of the coil winding range has a tip end portion formed on an inclined surface, so that there is no problem even when the wire rod is slightly misaligned and wound outside the range when the coil is wound. Will naturally descend the slope and be wound into the correct winding position. Further, since the tip of the flange is formed in a tapered shape, the state of close contact with the outer layer made of resin, which is coated on the outer side of the flange, is improved, and the ingress of water, salt water, etc. can be prevented. In particular, the tapered shape of the flange tip portion is formed by utilizing the inclined surface,
The two effects of preventing the entanglement and improving the adhesiveness can be easily realized with a single configuration. Also, water, salt water, etc. can be sufficiently prevented from entering the terminal side from the opening end of the remaining hole of the bobbin.

[Brief description of drawings]

FIG. 1 is a front view of a bobbin portion of a rotation sensor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a front view showing a cross section of an outer layer portion of the rotation sensor according to the present embodiment.

5 is an enlarged cross-sectional view of the main parts of FIG.

FIG. 6 is an enlarged cross-sectional view of another main part of FIG.

FIG. 7 is a sectional view of a rotation sensor according to another embodiment.

FIG. 8 is a sectional view of a conventional rotation sensor.

[Explanation of symbols]

1 pole body 2 magnets 3 bobbins 4 coil winding range 5 coils 6,7 flange 8 remaining holes 9 Water, salt water, etc. 14 slope 15 Tapered tip 16 tapered tip 17,18 Cable wire 19, 20 terminals 21 Outer layer 22, 23 Fusion part

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-312822 (JP, A) JP-A-4-132964 (JP, A) JP-A-48-60229 (JP, A) JP-A-8- 43415 (JP, A) Actual development 3-83875 (JP, U) Actual development 3-106456 (JP, U) Actual development Sho 63-81207 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01P 3/478-3/488 H01F 27/32

Claims (4)

(57) [Claims] 1. A bobbin made of resin for accommodating a pole body and a magnet, a coil wound around a coil winding portion provided on an outer surface of the bobbin, the bobbin and the coil being externally attached to the tip of the pole body. In a rotation sensor having a resin outer layer portion that covers the pole body and the magnet while protruding, a fixing member for fixing the position of the pole body and the magnet so as not to move by injection pressure during injection molding of the bobbin is obtained. A rotation sensor characterized in that a tip opening of a residual hole formed is formed in a tapered shape. 2. A bobbin made of resin for accommodating a pole body and a magnet, a coil wound around a coil winding portion provided on the outer surface of the bobbin, the bobbin and the coil being externally attached to the tip of the pole body. In a rotation sensor having a resin outer layer portion that covers the coil winding portion, a flange defining one end side of a winding range of the coil is located at a tip end side of the pole body in the coil winding portion. Is integrally formed on the bobbin, the tip end of the flange is formed as an inclined surface so that the coil side does not become entangled when the coil is wound, and is formed in a tapered shape by using the inclined surface. At the time of injection molding, the tip opening of the residual hole formed by taking out the fixing member for fixing the position of the pole body and the magnet so as not to move by the injection pressure is formed in a tapered shape. A rotation sensor characterized by being installed. 3. The rotation sensor according to claim 1 , wherein the taper-shaped portion of the bobbin is fused with an outer layer outside the bobbin. In any one of claims 4] claims 1-3, the distal end opening portion of the remaining holes, rotation sensor, characterized in that it is formed as an inclined surface descending toward the distal end of the pole body.