JP4643050B2 - Sensor waterproof structure and sensor including the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waterproof structure for a sensor and a sensor including the same. The waterproof structure of the sensor of the present invention is useful in various temperature sensors such as a water temperature sensor, an oil temperature sensor, an intake air temperature sensor, and an outside air temperature sensor that are disposed in a predetermined part of a vehicle or the like.
[0002]
[Prior art]
Conventionally, as shown in FIG. 7, an element lead wire 11 in which an insulating tube 112 is covered with a metal wire 111, a sensor element 12 such as a thermistor connected to one end thereof, and a metal wire connected to the other end. If necessary, the molded body 5 in which the sensor element 12 of the sensor element member including the harness lead wire 13 or the connector terminal covered with the insulating coating 132 and the other part except for the vicinity thereof is embedded as needed. Various sensors are formed by being incorporated in the metal case 6 or the like.
[0003]
[Problems to be solved by the invention]
However, the adhesion between the element lead wire and the harness lead wire or the connector terminal and the cured resin is not sufficient, and the vicinity of the portion where the harness lead wire is pulled out from the molded body or the portion where the connector terminal opens on the end surface of the molded body Moisture or the like may enter from the inside. Also, the production of a molded body integrally having a sensor element member requires complicated steps such as preparation of resin raw material, defoaming, casting into a mold, curing of resin raw material, and mold release, and workability is low. . Further, it is not easy to dispose the sensor element member at a predetermined position, and the sensor element may be damaged during the operation.
[0004]
The present invention solves the above-mentioned problems of the prior art, and uses a resin molded body and a resin member having a specific shape, and leads by a waterproof member disposed in a space formed by these. An object of the present invention is to provide a waterproof structure for a sensor that prevents moisture from entering the sensor element side through a wire. In addition, the sensor element of the sensor element member and other portions except for the vicinity thereof are disposed inside the resin member formed in a predetermined shape in advance, and further, in a space formed by the resin member and a resin molded body having a specific shape. An object of the present invention is to provide a sensor in which moisture is prevented from entering the inside by disposing a waterproof member.
[0005]
[Means for Solving the Problems]
The waterproof structure of the sensor of the first invention includes a resin molded body, a resin member in which a space is formed between the resin molded body on one side, and one end opened to the outside, and the resin so as to pass through the space. The lead wire disposed through the molded body and the resin member, the sensor element connected to the other end of the lead wire, the wall surface of the space, and the lead wire are opened to the outside by being in close contact with each other. A waterproof member for preventing moisture from entering from the one end side to the sensor element side ,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member, and a locking piece extends below the outer periphery of the resin molded body. A cutout portion is formed in the piece, and the cutout portion and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed. and said that you are.
[0006]
In the waterproof structure of the sensor according to the second aspect of the present invention, the connector terminal is formed on the other surface side of the resin molded body except the resin member side, and one end of the lead wire is connected to the connector pin held by the connector terminal. Other configurations are the same as those of the first invention.
[0007]
The sensor element is disposed in a sealed space where the temperature or the like is measured when the sensor having the waterproof structure is used. For example, the sensor element is disposed in a temperature measuring recess provided in an engine block or the like of the vehicle. When a metal case or the like is used, such as an intake air temperature sensor of a vehicle, it is disposed in a sealed space formed by the metal case and the “resin member”. In this sealed space, for example, in a temperature sensor, it is preferable to fill a silicone compound or the like having heat conductivity to improve the response of the sensor. Further, when the sensor element member is not sufficiently held and fixed by the resin member or the like, the sensor element member can be held and fixed by filling the sealed space with a thermosetting resin or the like and curing it.
[0008]
The sensor of the third invention is a sensor element, a lead wire having one end open to the outside and the sensor element connected to the other end, a resin member having a resin member through hole in which the lead wire is disposed, A resin molded body having a resin molded body through-hole in which the lead wire is disposed, and a resin molded body that forms a space through which the lead wire passes with the resin member, and is fitted into the lead wire in the space, A waterproof member that prevents water from entering from the one end side opened to the outside to the sensor element side by being in close contact with the wall surface and the lead wire ,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member, and a locking piece extends below the outer periphery of the resin molded body. A cutout portion is formed in the piece, and the cutout portion and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed. and said that you are.
[0009]
In the sensor according to the fourth aspect of the invention, the connector pin is held by the connector terminal formed on the resin molded body, and one end of the lead wire is connected to the connector pin. Other configurations are the same as those of the third invention.
The “lead wire” in the first to fourth inventions means both an element lead wire and a harness lead wire, and among them, the harness lead wire is in close contact with the “waterproof member”. It is.
[0010]
The resin member is not particularly limited as long as it can form a resin member through-hole for accommodating an element lead wire and, if necessary, a connecting portion of the lead wire inside. As the resin member, as in the fifth invention, it is preferable to use a half-shaped molded body in which a concave path for storing a lead wire or the like is formed on each mating surface. If it is a half type, the resin member which has a through-hole can be easily formed by match | combining each surface which has a concave path. When the sensor is used, the resin member is sealed in, for example, a sealed space to be temperature-measured or a metal case, so that it is not necessary to pay particular attention to preventing moisture from entering from the outside. Therefore, there is no problem at all even if the half type is used.
[0011]
The resin molded body only needs to have a shape that has a pull-out hole for pulling out the harness lead wire to the outside and can form a space that can accommodate the waterproof member between the resin member. Moreover, since this resin molded body is exposed to the outside air or the like when the sensor is used, it is preferable that the resin molded body can reliably prevent moisture or the like from entering from the outside. Therefore, in the case of a resin molded body that creates a gap on the molding surface, such as a half mold, it is necessary to apply an adhesive etc. to the mating surface and seal it. It is possible to form a space having
[0012]
In the waterproof structure of the first invention and the sensor of the third invention in which the harness lead wire is drawn out from the opening of the drawing hole provided in the resin molded body, it is essential to prevent moisture from entering the sensor element from this opening. It is. On the other hand, in the waterproof structure of the second invention in which the connector terminal is formed on the resin molded body and the sensor of the fourth invention, it is possible to more reliably prevent moisture from entering by using the waterproof external terminal. . Thus, the waterproof structure of the sensor of the present invention and the sensor including the same are particularly useful in the sensor with a lead wire in which the harness lead wire is connected to the element lead wire of the first and third inventions. Great action and effect can be obtained.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to examples.
Example 1 (Example relating to a sensor with a lead wire corresponding to the third invention)
(1) Manufacture of sensor A process of manufacturing a temperature sensor with a lead wire will be described with reference to FIGS.
(1) Mounting a waterproof member on the sensor element member (see FIG. 1)
The harness lead wire 13 of the sensor element member 1 is composed of an element lead wire 11, a temperature measuring element 12 comprising a thermistor connected to one end of the element lead wire 11, and a harness lead wire 13 connected to the other end. The waterproof member 2 made from the product was fitted.
[0014]
The waterproof member 2 is not particularly limited as long as the waterproof member 2 is moderately flexible and can prevent entry of moisture from the outside, and the material, shape, and the like are not particularly limited. In consideration of the wire diameter, material, etc., the waterproof member 2 made of silicon rubber or nitrile rubber is preferable.
[0015]
(2) Attaching the sensor element member to the half-shaped resin member (see FIGS. 2 and 3)
Recessed paths 311a, 311b and element lead wires 11 formed on the inner surfaces 31a and 31b of the half-shaped resin member 3 for forming through holes for accommodating the element lead wires 11, respectively. Sensor element prepared in (1) in any one of the recesses 312a and 312b for forming a through hole for accommodating the connecting portion 14 (see FIGS. 5 and 6) between the lead wire 13 and the harness lead wire 13. The member was fitted. Thereafter, the half mold was closed and fixed integrally with the locking members 33a, 33b, 33c, and 33d to obtain an intermediate product having the appearance shown in FIG.
[0016]
The half-shaped resin member can be easily molded by an injection molding method or the like using a synthetic resin such as polyamide, polyester, or polyolefin, including a concave path and a locking tool. A locking tool can be made into the shape which can be locked by fitting one recessed part and the other convex part of the shape corresponding to this.
In addition, in order to improve the intensity | strength etc. of a resin member, the reinforced resin which mix | blended required amount, for example, 10-50 mass%, especially 20-40 mass% glass fiber etc. can also be used.
[0017]
(3) Shape of resin molded body and fitting to resin member (see FIGS. 3 and 4)
A resin molded body 4 having the same shape as the outer surface and the same inner surface shape and dimensions as the outer surface of the resin member 3 was fitted on the side from which the harness lead wire 13 was drawn. A lead hole 41 (see FIGS. 5 and 6) for pulling out the harness lead wire 13 is provided on the upper surface of the resin molded body 4. In addition, a locking piece 42 having a notch 421 is extended below the outer periphery of the resin molded body 4 and is fitted with a locking projection 35 formed on the side surface of the resin member 3. 3 and the resin molded body 4 are fixed integrally. Further, when the sensor is mounted on the metal case or when the sensor is mounted on a recess provided in the engine block, the resin molded body 4 is reliably prevented from entering moisture and other sensor elements. A flange portion 43 that facilitates mounting of the O-ring is formed.
[0018]
(2) Structure of temperature sensor (see FIGS. 5 and 6)
The through-hole 32 formed in the resin member 3 accommodates the element lead wire 11 and the connection portion 14 between the element lead wire 11 and the harness lead wire 13. Further, the harness lead wire 13 is drawn out from a lead hole 41 formed on the upper surface side of the resin molded body 4 fitted to one end side of the resin member 3. As shown in FIG. 6, the resin member 3 and the resin molded body 4 are provided with locking projections 35 formed at two opposing positions on the side surface of the resin member 3 extending below the resin molded body 4. By being fitted into a notch 421 formed in the formed locking piece 42, it is fixed integrally.
[0019]
Further, the waterproof member 2 is fitted to the harness lead wire 13 in the space formed by the resin member 3 and the resin molded body 4. This space is formed with an inner diameter of 4.4 mmφ and a depth of about 7 mm, and the waterproof member 2 is pressed and adhered in the circumferential direction in this space. The waterproof member 2 reliably prevents moisture from entering the temperature measuring element 12 through the harness lead wire 13 from the lead hole 41 formed on the upper surface side of the resin molded body 4. Since the waterproof member 2 has a free diameter of 5.0 mmφ, the waterproof member 2 is pressed against the wall surface in the space while being crushed 0.6 mm in the circumferential direction.
[0020]
It should be noted that the present invention is not limited to the specific examples described above, and various modified examples can be made within the scope of the present invention depending on the purpose, application, and the like. For example, the through-hole formed in the resin member can be a wider space, and the element lead can be fixed by filling the space with an epoxy resin or the like. In addition, a half mold in which the resin member and the resin molded body are integrated can be used, and in this case, an adhesive or the like is applied to the mating surface of the portion corresponding to the half mold resin molded body, It is preferable to ensure waterproofness.
[0021]
【The invention's effect】
According to the 1st or 2nd invention, it can be set as the waterproof structure by which the penetration | invasion of the water | moisture content from the harness lead wire or the periphery of a connector terminal is fully prevented. In addition, according to the third to fifth inventions, the sensor can be easily manufactured with a simple process, and moisture can be reliably prevented from entering the inside.
[Brief description of the drawings]
FIG. 1 is a front view of a temperature measuring element with a lead wire in which a waterproof member is fitted to a harness lead wire.
FIG. 2 is a front view showing a state in which a half-shaped resin member having a recessed path for fitting and fixing a temperature measuring element with a lead wire is opened on the inner surface.
FIG. 3 is a front view of a resin member in which an element lead wire of a temperature measuring element with a lead wire and a connection portion between the element lead wire and a harness lead wire are fitted in an internal hole path.
FIG. 4 is a front view of a resin molded body fitted on an upper part of a resin member as viewed from the side on which a locking piece is formed.
FIG. 5 shows an element lead wire of a temperature measuring element with a lead wire and a connection portion between the element lead wire and a harness lead wire in a hole path inside the resin member, and a resin molding is fitted on the upper surface; It is sectional drawing which shows the state by which the harness lead wire was pulled out from.
6 is a cross-sectional view similar to FIG. 5, seen from the side on which the locking piece is formed. FIG.
FIG. 7 is a cross-sectional view of a conventional water temperature sensor in which a molded body in which a resin and a temperature measuring element with a lead wire are integrally molded by a molding die is housed in a metal case.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Sensor element member, 11; Element lead wire, 111; Metal wire, 112; Insulating tube, 12; Temperature measuring element, 13; Harness lead wire, 131; Metal wire, 132; Insulation coating, 14; Connection portion with harness lead wire, 2; waterproofing member, 3; half-split resin member, 31a, 31b; half-split inner surface, 311a, 311b; for forming a through hole for accommodating element lead wire Concave, 312a, 312b; Concave for forming a through hole for accommodating the connecting part, 32; Through hole, 33a, 33b, 33c, 33d; Locking tool, 34; Half-folded bent part, 35; Locking projection, 4; Resin molded body, 41; Pull-out hole, 42; Locking piece, 421; Notch, 43; Flange, 5; Resin molded body in which sensor element member is embedded, 6; Metal Case 7; O-ring.

Claims (5)

A resin member having a space formed between the resin molded body and the resin molded body on one side, and one end opened to the outside, penetrating the resin molded body and the resin member so as to pass through the space The arranged lead wire, the sensor element connected to the other end of the lead wire, and from the one end side opened to the outside by being in close contact with the wall surface of the space and the lead wire, to the sensor element side A waterproof member that prevents the intrusion of moisture ,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member,
A locking piece extends under the outer periphery of the resin molded body,
A notch is formed in the locking piece,
The waterproof structure for a sensor , wherein the cutout portion and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed. . A resin molded body, a resin member in which a space is formed between the resin molded body on one surface side, a connector terminal formed on the other surface side excluding the surface on the resin member side of the resin molded body, A connector pin held by the connector terminal, one end of which is connected to the connector pin, a lead wire disposed through the resin molded body and the resin member so as to pass through the space, and the lead wire A sensor element connected to the other end, and a waterproof member that prevents moisture from entering from the connector terminal side to the sensor element side by being in close contact with the wall surface of the space and the lead wire ,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member,
A locking piece extends under the outer periphery of the resin molded body,
A notch is formed in the locking piece,
The waterproof structure for a sensor , wherein the cutout portion and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed. . A sensor element; a lead wire having one end opened to the outside and the other end connected to the sensor element; a resin member having a resin member through-hole in which the lead wire is disposed; and the lead wire disposed A resin molded body having a resin molded body through-hole and forming a space through which the lead wire passes with the resin member, and fitted into the lead wire in the space, and is in close contact with the wall surface of the space and the lead wire A waterproof member that prevents moisture from entering from the one end side opened to the outside to the sensor element side ,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member,
A locking piece extends under the outer periphery of the resin molded body,
A notch is formed in the locking piece,
The sensor, wherein the notch and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed . A sensor element, a connector pin for transmitting a signal from the sensor element to the outside, a lead wire having one end connected to the connector pin and the other end connected to the sensor element, and a resin provided with the lead wire A resin member having a member through hole, a resin molded body having a resin molded body through hole in which the lead wire is disposed, and forming a space through which the lead wire passes with the resin member, and the resin molded body A waterproof terminal for preventing moisture from entering from the connector terminal side to the sensor element side by being formed and being in close contact with the wall surface of the space and the lead wire, the connector terminal holding the connector pin; equipped with a,
The resin molded body is fitted into the resin member so as to cover the one surface side of the resin member,
A locking piece extends under the outer periphery of the resin molded body,
A notch is formed in the locking piece,
The sensor, wherein the notch and a locking projection formed on a side surface of the resin member are fitted together, and the resin member and the resin molded body are integrally fixed .   A recess for forming the space is formed in the resin molded body or the resin member, the waterproof member is provided in the recess, and the resin member or the resin not provided with the waterproof member is provided. The sensor according to claim 3 or 4, wherein the molded body is formed of a half-shaped molded body, and the through-holes are formed by integrating recesses provided in each of the mating surfaces.

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