SENSOR DEVICE

An object is to further improve the waterproofness between an end portion of a wiring member and a resin molded part. Disclosed is a sensor device including: a sensor element; a wiring member connected to the sensor element; a first resin molded part that covers the sensor element and an end portion of the wiring member; and a second resin molded part molded separately from the first resin molded part and combined with the first resin molded part into an integral piece.

TECHNICAL FIELD

The present disclosure relates to a sensor device.

BACKGROUND

JP 2017-096828A discloses that a plurality of output wire parts are connected to a detection element part, the plurality of output wire parts being bundled as a sheath wire, and that the detection element part and an end portion of the sheath wire are embedded in a resin molded part.

For a configuration in which an end portion of a wiring member is embedded in a resin molded part, it is desired to further improve the waterproofness between the outer circumference of the wiring member and the resin molded part.

Therefore, an object of the present disclosure is to further improve the waterproofness between an end portion of a wiring member and a resin molded part.

SUMMARY

A sensor device according to the present disclosure is a sensor device including: a sensor element; a wiring member connected to the sensor element; a first resin molded part that covers the sensor element and an end portion of the wiring member; and a second resin molded part molded separately from the first resin molded part and combined with the first resin molded part into an integral piece.

Advantageous effects

According to the present disclosure, the waterproofness between an end portion of a wiring member and a resin molded part is further improved.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

First, aspects of the present disclosure will be listed and described.

A sensor device according to the present disclosure is as follows.

First Aspect

In a first aspect, a sensor device according to the present disclosure is a sensor device including: a sensor element; a wiring member connected to the sensor element; a first resin molded part that covers the sensor element and an end portion of the wiring member; and a second resin molded part molded separately from the first resin molded part and combined with the first resin molded part into an integral piece. According to this sensor device, the thermal effect on the wiring member is reduced since the first resin molded part and the second resin molded part are molded separately. This results in, for example, suppression of the contraction of the wiring member, and reduction of sink marks due to a reduced thickness of the resin portion, thus making it possible to further improve the waterproofness between the end portion of the wiring member and the resin molded part. In addition, as a result of the first resin molded part and the second resin molded part being combined, a desired shape as the sensor device is formed.

Second Aspect

In a second aspect of the sensor device in accordance with the first aspect, the first resin molded part and the second resin molded part may separately and directly cover regions of the end portion of the wiring member that are different in an extension direction of the wiring member. The length by which each of the first resin molded part and the second resin molded part directly covers the end portion of the wiring member is reduced. Accordingly, when molding the first resin molded part and the second resin molded part, it is possible to eliminate or reduce the locations at which the wiring member is positioned within a mold space. This further improves the waterproofness.

Third Aspect

In a third aspect of the sensor device in accordance with the second aspect, the first resin molded part and the second resin molded part continuously may cover the end portion of the wiring member. Since the first resin molded part and the second resin molded part continuously cover the end portion of the wiring member, the waterproofness is further improved.

Fourth Aspect

In a fourth aspect of the sensor device in accordance with any one of the first to the third aspects, the first resin molded part may include a plurality of resin-stopping annular protrusions, and the second resin molded part may cover a portion of the first resin molded part while the second resin molded part is continuous with one of the plurality of resin-stopping annular protrusions. The region in which the second resin molded part covers the first resin molded part can be flexibly adjusted using the plurality of resin-stopping annular protrusions.

Fifth Aspect

In a fifth aspect of the sensor device in accordance with the fourth aspect, the plurality of resin-stopping annular protrusions may include a first resin-stopping annular protrusion, and a second resin-stopping annular protrusion formed at a position more distant from the sensor element than the first resin-stopping annular protrusion is, and the second resin molded part may cover a portion of the first resin molded part that extends from the second resin-stopping annular protrusion toward a side on which the wiring member extends. A portion located away from the sensor element can be covered by the second resin molded part.

Sixth Aspect

In a sixth aspect of the sensor device in accordance with the fourth aspect, the plurality of resin-stopping annular protrusions may include a first resin-stopping annular protrusion, and a second resin-stopping annular protrusion formed at a position more distant from the sensor element than the first resin-stopping annular protrusion is, and the second resin molded part may cover a portion of the first resin molded part that extends from the first resin-stopping annular protrusion toward a side on which the wiring member extends. A portion located close to the sensor element can be covered by the second resin molded part.

Specific examples of the sensor device according to the present disclosure will be described below with reference to the drawings. It should be noted that the present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications which fall within the scope of the claims and the meaning and scope of equivalents thereof.

Embodiment

A sensor device according to an embodiment will be described below. FIG.1is a front view showing a sensor device10.FIG.2is a cross-sectional view taken along the line II-II inFIG.1.FIG.3is a cross-sectional view taken along the line III-III inFIG.1. InFIG.2, an outer shape, rather than a cross section, is shown for a sensor element20, an inner holder part40, and a wiring member30.

The sensor device10includes a sensor element20, a wiring member30, a first resin molded part50, and a second resin molded part60. The sensor element20is connected to the wiring member30. The first resin molded part50covers the sensor element20and an end portion of the wiring member30. The second resin molded part60is a portion molded separately from the first resin molded part50. The second resin molded part60is combined with the first resin molded part50into an integral piece. The first resin molded part50and the second resin molded part60are molded separately, and constitute an integral resin molded part and cover the sensor element20and the end portion of the wiring member30.

More specifically, the sensor element20is an element that detects a physical quantity such as magnetism, light, and temperature, or an amount of change thereof. Here, the sensor element20includes an element main body part22and a lead part24. The element main body part22is formed in a square shape, for example. The lead part24is an elongated portion made of metal or the like. The lead part24extends outward from the element main body part22. An output signal from the sensor element20is output to an external device via the lead part24. The sensor device10can be used, for example, as a sensor that detects a rotational speed of a wheel in a vehicle. More specifically, the sensor device10may be used as a sensor for an ABS (anti-lock brake system).

The wiring member30is connected to the sensor element20. The wiring member30includes at least one linear conductor. Here, the wiring member30includes a plurality of (here, two) wires32. Each wire32includes a core wire32aserving as a conductor, and an insulating covering32bsurrounding the core wire32a. The plurality of wires32are covered by a sheath34in a state in which they are bundled together. The sheath34is a covering made of resin or the like. The plurality of wires32extend from an end of the sheath34. Each of the core wires32ais exposed at an end portion of the corresponding one of the plurality of wires32. The core wires32aat the respective end portions of the plurality of wires32are connected to the lead part24. The connection between the core wires32aand the lead part24may be achieved through soldering or crimping, for example. The wiring member may be constituted by a single wire. The wiring member may be a member formed by a plurality of wires that are bundled so as to be exposed without being covered by the sheath.

The first resin molded part50covers the sensor element20and the end portion of the wiring member30. Here, the sensor element20, and the connection portion between the sensor element20and the wiring member30are held in a fixed orientation by an inner holder part40. For example, the inner holder part40is a resin molded portion molded using, as insert portions, the sensor element20, and the connection portion between the lead part and the core wire32a. A component in which the sensor element20, and the connection portion between the sensor element20and the wiring member30are held by the inner holder part40may be considered as an intermediate component40M. By molding the first resin molded part50using such an intermediate component40M as an insert portion, the sensor element20is embedded at a correct position in the first resin molded part50. By molding the first resin molded part50so as to cover the inner holder part40, the waterproofness for the sensor element20is increased. It is not essential that the inner holder part40is a component formed by molding using the sensor element20and so forth as an insert portion. For example, the inner holder part40may be molded in a shape that enables the sensor element20and so forth to be fitted therein, and the sensor element20and the like may be fitted therein. It is also not essential that the sensor device10includes the inner holder part40. The first resin molded part50may directly cover the sensor element20.

The first resin molded part50covers the sensor element20via the inner holder part40. In addition, the first resin molded part50covers an end portion of the wiring member30, here an end portion of the sheath34. That is, the first resin molded part50covers a portion extending from the sensor element20to an end portion of the sheath34. Such a first resin molded part50is a member that covers the sensor element20and an end portion of the wiring member30that is connected to the sensor element20so as to maintain the sensor element20and the end portion in a fixed positional relationship.

The second resin molded part60is a portion molded separately from the first resin molded part50and is combined with the first resin molded part50into an integral piece. Since the first resin molded part50and the second resin molded part60are molded separately, it is considered that a boundary appears between the first resin molded part50and the second resin molded part60even if they are made of the same material.

The first resin molded part50and the second resin molded part60separately and directly cover regions of the end portion of the wiring member30that are different in the extension direction of the wiring member30. Here, the second resin molded part60covers a portion of the first resin molded part50on a side on which the wiring member30extends. Additionally, the second resin molded part60extends, relative to the first resin molded part50, to the side on which the wiring member30extends, and also covers the sheath34of the wiring member30that extends from the first resin molded part50. That is, of the end portion of the wiring member30connected to the sensor element20, a portion located closer to the sensor element20is directly covered by the first resin molded part50, and a portion located more distant from the sensor element20is directly covered by the second resin molded part60.

It is not essential that the first resin molded part50and the second resin molded part60separately and directly cover an end portion of the wiring member30. For example, the second resin molded part may be formed on an outer circumferential side of the first resin molded part, and need not directly cover the wiring member. It is also not essential that the second resin molded part60covers the first resin molded part50. For example, the second resin molded part may be continuous with an end portion of the first resin molded part that is located on a side on which the wiring member extends.

The first resin molded part50continuously covers the end portion of the wiring member30in the extension direction of the wiring member30, and the second resin molded part60also continuously covers the end portion of the wiring member30in the extension direction of the wiring member30. Here, the expression that the first resin molded part50or the second resin molded part60continuously covers the end portion of the wiring member30means that the first resin molded part50or the second resin molded part60covers the end portion of the wiring member30without exposing the wiring member30at any midpoint thereof. That is, no marks of positioning pins for positioning the wiring member30when molding the first resin molded part50and the second resin molded part60are present at any midpoint in the first resin molded part50and the second resin molded part60.

A fixed part38is fixed to the second resin molded part60. Here, the fixed part38is fixed to a longitudinal intermediate portion of the second resin molded part60. The fixed part38includes a sensor-side fixed part38afixed around the second resin molded part60, and a vehicle body-side fixed part38bprotruding outward from the sensor-side fixed part38a. The sensor-side fixed part38ahas a through hole38ahin which the second resin molded part60is to be disposed. The vehicle body-side fixed part38bhas a screw fastening hole38bh. The second resin molded part60may be molded while the fixed part38is positioned within a mold. This allows the fixed part38to be fixed to an outer circumferential portion of the second resin molded part60. The fixed part38may be fixed to the second resin molded part60by fitting the second resin molded part60to the through hole38ahof the fixed part38. Thus, the second resin molded part60may be considered as a portion that forms a shaped portion for fixing the fixed part38.

With the sensor device10configured in this manner, the first resin molded part50and the second resin molded part60are molded separately, and therefore the thermal effect on the wiring member30is reduced. For example, when portions respectively corresponding to the first resin molded part50and the second resin molded part60are molded as a single resin molded part, a heated resin melt is supplied around the wiring member30in an amount corresponding to the first resin molded part50and the second resin molded part60. This may increase the thermal effect on the wiring member30. In contrast, when the first resin molded part50and the second resin molded part60are molded separately, a heated resin melt in an amount corresponding to the first resin molded part50, and a heated resin melt in an amount corresponding to the second resin molded part60are supplied around the wiring member30in separate occasions. Accordingly, the amount of heat applied to the wiring member30is reduced, and the length of time during which the wiring member30is kept at high temperature is also reduced. This reduces the thermal effect on the wiring member30. Accordingly, the thermal expansion of the wiring member30is suppressed, and the contraction of the wiring member30after thermal expansion is also suppressed. By supplying the heated resin melt in separate occasions, it is possible to reduce the thickness of the first resin molded part50, thus reducing sink marks. As a result of these, the adhesion between the wiring member30and the first resin molded part50is improved, and the waterproofness between the end portion of the wiring member30and the first resin molded part50is further improved. Similarly, the adhesion between the wiring member30and the second resin molded part60is improved, and the waterproofness between the end portion of the wiring member30and the second resin molded part60is further improved. As a result of the first resin molded part50and the second resin molded part60being combined, a desired shape as the sensor device10is formed. For example, a shape is achieved in which the shape of the wiring member30extending from the sensor element20is kept constant by the first resin molded part50, and the fixed part38is held in a predetermined orientation at a predetermined position by the second resin molded part60.

As a result of the first resin molded part50and the second resin molded part60separately and directly covering the respective regions of the end portion of the wiring member30that are different in the extension direction of the wiring member30, the length by which each of the first resin molded part50and the second resin molded part60directly covers the end portion of the wiring member30is reduced. Accordingly, when molding the first resin molded part50and the second resin molded part60, it is possible to eliminate or reduce the locations at which the wiring member30is positioned within a mold space. This further improves the waterproofness.

In this case, an exterior member such as a tubular elastic member or adhesive tape may be externally attached to the end portion of the wiring member, and the exterior member may constitute a portion of the wiring member. In this case, at least one of the first resin molded part50and the second resin molded part60directly covers the wiring member by directly covering the exterior member.

As described above, when the length by which the wiring member30is held is reduced in the first resin molded part50and the second resin molded part60, and thus the need to provide a positioning pin is eliminated, it is possible to easily realize a configuration in which the first resin molded part50and the second resin molded part60continuously cover the end portion of the wiring member30as in the case of the embodiment. This further improves the waterproofness between the wiring member30and each of the first resin molded part50and the second resin molded part60.

In the sensor device10described above, the first resin molded part50includes a plurality of resin-stopping annular protrusions56and58. Here, the plurality of resin-stopping annular protrusions56and58include a first resin-stopping annular protrusion56and a second resin-stopping annular protrusion58. In a direction in which the wiring member30extends from the sensor element20, the distance to the sensor element20is different between the first resin-stopping annular protrusion56and the second resin-stopping annular protrusion58. The second resin-stopping annular protrusion58is formed at a position more distant from the sensor element20than the first resin-stopping annular protrusion56is.

Here, the first resin-stopping annular protrusion56is formed on the first resin molded part50at a portion in which the element main body portion is embedded. The first resin-stopping annular protrusion56is formed in the shape of an annular projection protruding outward in the outer circumferential direction of the first resin molded part50. A surface of the first resin-stopping annular protrusion56that is located on a side on which the wiring member30extends is formed as a sealing surface56fthat extends gradually away from the wiring member30toward the outer side in a protruding direction (outer circumferential side) thereof. The sealing surface56fis also formed in an annular shape in the circumferential direction of the first resin-stopping annular protrusion56.

The second resin-stopping annular protrusion58is provided on the first resin molded part50at a position away from the side on which the wiring member30extends from the sensor element20. Here, the second resin-stopping annular protrusion58is formed at a longitudinal intermediate portion of the first resin molded part50. The second resin-stopping annular protrusion58is formed in the shape of an annular projection protruding outward in the outer circumferential direction of the first resin molded part50. A surface of the second resin-stopping annular protrusion58that is located on a side on which the wiring member30extends is formed as a sealing surface58fthat extends gradually away from the wiring member30toward the outer side in a protruding direction (outer circumferential side) thereof. The sealing surface58fis also formed in an annular shape in the circumferential direction of the second resin-stopping annular protrusion58.

The second resin molded part60covers a portion of the first resin molded part50while the second resin molded part60is continuous with one of the plurality of resin-stopping annular protrusions56and58. In the present embodiment, the second resin molded part60covers a portion of the first resin molded part50that extends from the second resin-stopping annular protrusion58toward a side on which the wiring member30extends, and also covers an end portion of the wiring member30that extends from the first resin molded part50.

The second resin-stopping annular protrusion58described above can serve the function of separating the mold space and the external space from each other when molding the second resin molded part60, thus suppressing leakage of the heated resin melt filled in the mold space to the outside.FIG.4is a diagram illustrating an example of a step of molding the second resin molded part60.

As shown inFIG.4, when molding the second resin molded part60, the first resin molded part50that covers the intermediate component40M and so forth needs to be positioned relative to a mold90. In this case, a portion of the first resin molded part50is disposed inside the mold space of the mold90, and another portion of the first resin molded part50is disposed in an external space that is located externally to the mold space. At a portion of the first resin molded part50that protrudes from the mold space, a gap through which the resin contained in the mold space leaks is preferably closed as soon as possible. Therefore, the second resin-stopping annular protrusion58is disposed outside the mold90, and the sealing surface58fof the second resin-stopping annular protrusion58is pressed against the mold90(see arrows P). Accordingly, the gap between the mold90and the first resin molded part50can be closed as soon as possible.

The plurality of resin-stopping annular protrusions56and58described above are useful for forming second resin molded parts having shapes that are different from each other. That is, as described above, as a result of the first resin molded part50and the second resin molded part60being combined, a desired shape as the sensor device10is formed, and the holding position or the like of the fixed part38is determined by the second resin molded part60, for example. It is conceivable that, as in the case of a sensor device110shown inFIG.5, the holding position or the like of the fixed part38is changed by changing the second resin molded part60to a second resin molded part160having a different shape. In the example shown inFIG.5, a first resin molded part50has the same configuration as that of the first resin molded part50of the sensor device10described above. The second resin molded part160corresponding to the second resin molded part60covers a portion of the first resin molded part50that extends from the first resin-stopping annular protrusion56toward a side on which the wiring member30extends, and also covers an end portion of the wiring member30that extends from the first resin molded part50. A second resin-stopping annular protrusion58is embedded in the second resin molded part160. A fixed part38is fixed to a longitudinal intermediate portion of the second resin molded part160. More specifically, a sensor-side fixed part38aof the fixed part38is fixed between the first resin-stopping annular protrusion56and the second resin-stopping annular protrusion58. For example, when molding the second resin molded part160, the sensor-side fixed part38ais fixed to the second resin molded part160by molding the second resin molded part160while the sensor-side fixed part38ais positioned inside a mold190. The fixed part38of the sensor device110may be the same as, or different from the fixed part38of the sensor device10.

The first resin-stopping annular protrusion56described above can serve the function of separating the mold space and the external space from each other when molding the second resin molded part160, thus suppressing leakage of the heated resin melt filled in the mold space to the outside.FIG.6is a diagram illustrating an example of a step of molding the second resin molded part160.

As shown inFIG.6, when molding the second resin molded part160, the first resin molded part50that covers the intermediate component40M and so forth needs to be positioned relative to a mold190. In this case, a portion of the first resin molded part50is disposed inside the mold space of the mold190, and another portion of the first resin molded part50is disposed in an external space that is located externally to the mold space. The second resin molded part160covers the first resin molded part50in more regions than the second resin molded part60described above. Accordingly, more portions of the first resin molded part50are disposed inside the mold190. At a portion of the first resin molded part50that protrudes from the mold space, a gap through which the resin contained in the mold space leaks is preferably closed as soon as possible. However, the position at which the first resin molded part50protrudes from the mold space is different from the position shown inFIG.4. When molding the second resin molded part160, the first resin-stopping annular protrusion56is disposed outside the mold190, and the sealing surface56fof the first resin-stopping annular protrusion56is pressed against the mold190(see arrows P). Accordingly, the gap between the mold190and the first resin molded part50can be closed as soon as possible. Thus, the resin for molding the second resin molded part160is less likely to leak from the mold190to the outside.

Since the first resin molded part50includes the plurality of resin-stopping annular protrusions56and58in this manner, the region in which each of the second resin molded parts60and160covers the first resin molded part50can be flexibly adjusted. Accordingly, the second resin molded parts60and160having different shapes can be easily formed for the same first resin molded part50. The second resin molded parts60and160having different shapes can contribute to changing of the fixing position or the like of the fixed part38, for example.

In particular, since the first resin-stopping annular protrusion56and the second resin-stopping annular protrusion58are formed at different distances to the sensor element20, the second resin molded part60that covers a portion of the first resin molded part50that is located away from the sensor element20, and the second resin molded part160that covers a portion of the first resin molded part50that is located close to the sensor element20can be selectively molded. By varying the region in which the second resin molded parts60and160are formed, the fixing position of the fixed part38can be set to be close to the sensor element20, or to be distant from the sensor element20.

The configurations described in the embodiment and the modification may be combined as appropriate as long as there are no mutual inconsistencies.