JPH1123379A - Temperature sensor - Google Patents

Abstract

(57) [Problem] To provide a temperature sensor that is fixed to a device and can be used in a stable state for a long time without applying a load to a cover by a clamp of only a main body of the temperature sensor. A temperature sensor (S) includes a head (3a) of a main body (3).
The cover 5 has a wire cover portion 51 that covers the lead wire 4 fitted into the wire fixing groove 31, and the head 3a of the main body 3 has a wire cover portion. The portion other than the portion covered by 51 has an exposed surface 30 exposed from the cover 5. The exposed surface 30 is a load supporting surface that transmits a load applied to the temperature sensor S to a fixture for the device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor and, more particularly, to a technique for attaching a temperature sensor to a device and preventing a lead wire from being removed.

[0002]

2. Description of the Related Art Conventionally, as a temperature sensor incorporated in an engine, an automatic transmission, or the like mounted on a vehicle and detecting an oil temperature for control thereof, there is a temperature sensor having a temperature sensing part as a thermistor. When a detected signal is taken out through a lead wire in such a temperature sensor, generally,
A thermistor and a pair of terminals each having one end connected to each of its poles are molded into a resin by insert molding to form a main body, and the other ends of the pair of terminals are exposed from the main body. In order to take out a signal with a lead wire whose tip is connected to the exposed portion of the connector, the connection portion is covered with a cover fitted to the main body in order to prevent foreign matter from entering the connection portion.

In such a temperature sensor, the other end of the terminal and the tip of the lead wire are connected by soldering.
Since the connection strength of the soldered portion tends to decrease due to deterioration with time, even if a tensile force acts on the lead wire, it must be prevented from acting on the soldered portion. Therefore, according to the technique disclosed in Japanese Utility Model Laid-Open No. 5-36330, a groove d having a bent portion c is formed in a side portion b of a sensor body a, and a lead wire e is fitted into the groove d, as shown in FIG. Thus, a configuration is adopted in which the action of a tensile force on the soldering portion due to the axial displacement of the lead wire e due to an external force is prevented. More specifically, the bent portion c is configured so that the axis of the lead wire e is partially shifted in parallel and laterally, and the frictional resistance between the coating of the lead wire e and the groove d is increased to prevent displacement in the axial direction. In. Furthermore, in this temperature sensor, in order to prevent the lead wire e from coming off the groove d, the entire surface of the main body a on which the lead wire e is fitted is covered with a cover.

When the temperature sensor having such a configuration is used as an oil temperature sensor to detect, for example, the oil temperature of an automatic transmission, the temperature sensor is fixed to a valve body by a special spring steel clamp, and the ambient temperature inside the oil pan is detected. Is arranged to detect In that case, the clamp will support the body and cover of the temperature sensor.

[0005]

When the temperature sensor as described above is used for detecting the oil temperature in the oil passage of the valve body, the hydraulic pressure acts directly on the temperature sensor, unlike the above-mentioned usage. A large load is applied to the clamp portion of the cover which is weaker in strength than the main body, which causes a problem in the durability of the cover.

SUMMARY OF THE INVENTION Accordingly, it is a first object of the present invention to provide a temperature sensor which can be fixed and used for a long time in a stable state without applying a load to a cover by a clamp of only a main body.
The purpose of.

Next, in a case where a configuration is adopted in which only the main body is clamped so as not to apply a load to the cover, in order to expose the main body from the cover, the lead wire is pressed into the groove by a partial cover portion to prevent the main body from coming off. In this case, however, it is difficult to make the retaining structure stronger.

Accordingly, a second object of the present invention is to ensure that the lead wire is securely prevented from falling off by firmly fitting a cover portion for covering and preventing the lead wire from coming off.

[0009] The temperature sensor incorporated in the device is
It is desirable that the lead wire is small and lightweight. However, in the lead wire misalignment prevention structure according to the conventional technique described above, the bent portion c is formed in the groove into which the lead wire is fitted, so that the bent portion c is matched with the groove forming side surface of the main body a. Required width and length. Therefore, this configuration is not suitable for use in a sensor having a small body.

Accordingly, a third object of the present invention is to prevent the lead wire from being displaced in the axial direction without bending the groove, thereby using a small groove forming surface.

By the way, when a temperature sensor is incorporated into a device, if only a single clamping method can be adopted, a clamp having a special shape must be used depending on the mounting position. The disadvantage of requiring a large occupied space for the clamp arises.

Accordingly, a fourth object of the present invention is to make the temperature sensor versatile by allowing the temperature sensor to be fixed to the device by using two different types of clamping methods.

[0013]

In order to achieve the first object, the present invention provides a main body including a temperature sensing part and a terminal connected to the temperature sensing part, and a lead wire connected to the terminal. When,
A cover fitted to the main body and covering at least a connection portion between the terminal and the lead wire, wherein the main body has a wire fixing groove for fitting the lead wire to a head thereof, and the cover is A wire cover that covers a lead wire fitted into the wire fixing groove, and the head of the main body has an exposed surface exposed from the cover in a portion other than the portion covered by the wire cover.

Next, in order to achieve the second object, the main body has a wire fixing groove inside and a wire cover fixing groove outside the main body, and the wire cover is formed in the wire cover fixing groove. It is configured to be fixed in a dovetail shape to prevent the lead wire from coming off.

Further, in order to achieve the third object, the wire fixing groove has an axial displacement preventing means for locally crushing a lead wire fitted in the wire fixing groove in a radial direction.

Next, in order to achieve a fourth object, the main body is configured to have a fitting groove of a fixture for fixing to a device on a side portion thereof.

[0017]

According to the temperature sensor according to the first aspect of the present invention, since the head has an exposed surface, the load is applied to the cover by pressing the exposed surface with an appropriate fixing tool. It can be fixed to the device without the need.
Therefore, according to the present invention, it is possible to improve the durability of the temperature sensor and detect the oil temperature stably over a long period of time.

Next, according to the second aspect of the present invention, the wire cover is fixed to the wire cover fixing groove of the main body in a dovetail shape, so that the wire cover partially covering the main body is securely fixed to the main body. The lead wire is pressed down, and is reliably prevented from coming off.

Further, in the configuration according to the third aspect, since the axial fixing means for locally crushing the lead wire in the radial direction is provided in the wire fixing groove, the misalignment of the lead wire is fitted. This can be performed without bending the wire fixing groove, whereby the wire fixing groove forming surface of the main body can be reduced.

Further, in the configuration according to the fourth aspect, since the fitting groove of the fixture is provided on the side of the main body in addition to the exposed surface of the head of the main body, the temperature sensor is fixed to the device. In addition, a method in which the head of the main body is pressed and a method in which an appropriate fixing means is fitted into the fitting groove in the side of the main body can be selected, whereby the versatility of the temperature sensor can be improved.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of a temperature sensor according to an embodiment. The sensor S includes a temperature sensing unit 1 having a built-in thermistor (not shown) and a pair of sensors connected to both poles of the thermistor of the temperature sensing unit 1. Are connected to the main body 3 molded by insert molding and the exposed portions 21 of the terminals 2 from the main body 3. And a pair of lead wires 4 and the main body 3
It mainly comprises a cover 5 for covering a connection portion T between both terminals 2 and both lead wires 4.

According to the present invention, the main body 3 has a wire fixing groove 31 on the head 3a of which the lead wires 4 are fitted in parallel with each other. On the other hand, the cover 5 has a wire cover portion 51 that covers the lead wire 4 fitted into the wire fixing groove 31. In this embodiment, the wire cover portion 51 has a shape extending in a comb-like shape on the upper surface of the cover 5, whereby the head 3 of the main body 3 is formed.
“a” has the exposed surface 30 exposed from the cover 5 in a portion other than the portion covered with the wire cover portion 51.

Further, the main body 3 has a wire fixing groove 31 inside and a wire cover fixing groove 32 outside. The wire cover 51 is fixed to the wire cover fixing groove 32 in a dovetail manner to prevent the lead wire 4 from coming off. That is, the comb tooth-shaped wire cover portion 51 has a dovetail shape in which the lower side is widened when viewed in cross section, and the wire cover portion fixing groove 32 has an inwardly wide groove width corresponding to the cross section of the wire cover portion. It has a dovetail groove shape with a cross section.

Further, the wire fixing grooves 31 have axial displacement preventing means for locally crushing the coating of the lead wire 4 fitted in them in the radial direction. FIG. 2 shows a specific shape of the slip-stopping means. In this case, the slip-stopping means has a saw-tooth shape having a plurality of edge portions 31a protruding toward both side walls of the wire fixing groove 31. I have.
Thus, even if a tensile force is applied to the lead wire 4 in the direction indicated by the arrow, the force is not directly applied to the connection portion T by soldering.

The main body 3 has a fitting groove 33 of a fixture for fixing to a device on a side portion (a specific position will be described later) which is not covered with the cover 5. In this embodiment, the fitting groove 33 is a parallel groove in which the main body 3 is cut out.

The respective parts will be described in more detail.
It is composed of a cylindrical shaft portion 3c inserted into the fitting hole of the device, a rectangular block-shaped head portion 3a, and a flange portion 3b serving as a means for positioning the mounted device between them.
A temperature-sensitive portion 1 having a smaller diameter and a dome-shaped tip than the shaft portion 3c is provided at the tip of the shaft portion 3c, and a fitting groove 34 for the O-ring 6 is formed in the middle of the shaft portion 3c. In addition, the flange 3
b is a configuration in which a part of the disk is cut in parallel to have a two-sided width, and the two-sided width part is relatively recessed into the shaft portion 3c and the head portion 3a. 33.
A groove 35 into which a flange portion 52 (see FIG. 3) projecting inward from both side walls of the cover 5 is formed below both side surfaces of the head 3a, and a rectangular fitting protrusion 36 is formed in a central portion. Is provided. Further, a vertical groove 37 into which a partition described later of the cover 5 is fitted is formed on the end surface on the side where the terminal 2 is exposed.

The cover 5 is applied to one side of the head 3a of the main body 3 so as to be understood by referring to the horizontal cross section at the center shown in FIG. 5a
The part fitted to the main body 3 connected thereto is a lid-like portion 5b whose front and lower parts are open. Box-shaped part 5a
Is provided with a partition wall 53 in such a manner as to vertically divide the inside thereof into two parts, and the distal end of the partition wall 53 terminates at a position where the partition wall 53 fits into the vertical groove 37 of the main body 3. Window holes 54 are formed on both side walls of the cover 5 so that the fitting protrusions 36 are fitted. The upper wall of the cover 5 is comb-shaped as described above except for the box-shaped portion 5a. In addition, the tip of the wire cover portion 51 formed as a comb tooth is rounded so as to reduce the corner on the lower surface side so as not to damage the coating of the lead wire 4.

In the temperature sensor composed of the above-described components, both the lead wires 4 are fitted into the wire fixing grooves 31, and the conductive wire portion 41 from which the coating of the lead wires 4 has been removed is bent and inserted into the hole of the terminal 2 and soldered. You. Then, the cover 5 is fitted to the main body 3 so as to cover the soldered connection portion T.
At this time, the flange 52 below the cover 5 is in the groove 35, the wire cover 51 is in the wire cover fixing groove 32,
The distal end portion of the main body 3 and the cover 5 are integrated with the vertical groove 37 and the window hole 54 with the fitting projection 36, respectively. The O-ring 6 is fitted into the fitting groove 34 as an outer peripheral seal of the shaft portion 3c.

Using the above configuration, the temperature sensor S
Or it is fixed to the device in two different forms as shown in FIG. First, in the fixing method shown in FIG. 4, the shaft portion 3c is inserted into the fitting hole H formed in the wall surrounding the oil passage L of the device so that only the temperature sensing portion 1 of the temperature sensor S projects into the oil passage L. Insert
In this state, a fixing method of pressing down the exposed surface 30 of the main body head 3a of the temperature sensor S by using an arbitrary surface of the component F parallel to the sensor mounting surface is adopted. According to this fixing method, the hydraulic pressure applied to the sensor S is supported by the component F through the main body 3, so that no load is applied to the cover 5. In the drawings, the exposed surface 30 of the main body head 3a from the cover 5 is emphasized so as to protrude significantly from the upper surface of the cover 5,
The amount of protrusion is sufficient if the exposed surface 30 does not become lower than the upper surface of the cover 5 in consideration of manufacturing errors, whereby the load supporting function by the exposed surface 30 is achieved.

Next, in the method shown in FIG.
In the fitting groove 33 (see FIG. 1) of the temperature sensor S inserted into the fitting hole H, the forked portion of the keep plate P having a forked tip is sandwiched by the flange portion 3b. Then, the keep plate P is fixed to the device with bolts B or the like. According to this method as well, the oil pressure applied to the sensor S is maintained through the main body 3 and the keep plate P
Specifically, the shaft portion 3c is supported by the forked portion of the keep plate P, so that no load is applied to the cover 5.

Finally, an application example in which the mounting object is further embodied will be described. In this case, the temperature sensor is incorporated in a transmission case C of the automatic transmission as shown in FIG. In this example, the temperature sensor S is attached to a discharge oil passage connected to a discharge side of an oil pump (not shown) in order to detect an oil temperature of an oil passage L in a valve body V of the automatic transmission. The temperature sensor S is fixed below the transmission case C and is fitted in an inverted state into the valve body V covered by the oil pan P, and the strainer F attached to the lower side of the valve body V is used as a fixture. The head is fixed with the head pressed down from below. The lead wire 4 of the temperature sensor S thus attached is guided to the wire connector N through the oil pan P, where it is connected to a socket inside the case of the wire connector N fixed to the case C so as to penetrate the transmission case C. Connected. A wire harness W connected to an electronic control unit (ECU) of the automatic transmission is connected to a socket of the wire connector N outside the transmission case. Thus, the oil temperature signal detected by the temperature sensor S can be transmitted to an electronic control unit (ECU) as an electric signal. Note that the detected oil temperature in this case is information for knowing the viscosity of the automatic transmission operating oil (ATF) necessary for the automatic transmission control.

As described in detail above, in this temperature sensor S, since the head 3a of the main body 3 has the exposed surface 30, the load is applied to the cover 5 by pressing the exposed surface 30 with an appropriate fixture. Therefore, the temperature sensor S can be improved in durability and stable oil temperature can be detected over a long period of time. Furthermore, in addition to the exposed surface 30 of the main body head 3a, a fitting groove 33 of a fixture is provided on the side of the main body, so that the head 3a of the main body 3 is fixed to fix the temperature sensor S to the device. It is possible to select between a pressing method and a method in which an appropriate fixing means is fitted in the fitting groove 33 on the side of the main body, thereby increasing the versatility of the temperature sensor S.

As described above, the present invention has been described in detail based on one embodiment. However, the present invention is not limited to only the disclosed contents of the above-described embodiment, and various details can be set within the scope of the claims. Needless to say, the present invention can be implemented by changing the specific configuration.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a temperature sensor according to an embodiment of the present invention.

FIG. 2 is a plan view of a sensor head showing a lead wire deviation preventing means of the temperature sensor.

FIG. 3 is a cross-sectional view of a cover of the temperature sensor.

FIG. 4 is an explanatory diagram showing a fixing method of the temperature sensor.

FIG. 5 is an explanatory view showing another embodiment of the fixing method.

FIG. 6 is an explanatory diagram of an arrangement of the temperature sensor in an automatic transmission.

FIG. 7 is a plan view showing a conventional temperature sensor.

[Explanation of symbols]

 S Temperature sensor T Connection part 1 Temperature sensing part 2 Terminal 3 Main body 3a Head 4 Lead wire 5 Cover 30 Exposed surface 31 Wire fixing groove 31a Displacement prevention means 32 Wire cover fixing groove 33 Fitting groove 51 Wire cover

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Katsutoshi Komatsu 10th Takane, Fujiimachi, Anjo, Aichi Prefecture Inside Aisin AW Co., Ltd. (72) Akira Fukatsu 10th Takane, Fujiimachi, Anjo, Aichi Aishi Inside AW Co., Ltd. (72) Inventor Toshiyuki Mae 10 Takane, Fujii-cho, Anjo-shi, Aichi Prefecture Inside AIC-AW Co., Ltd. (72) Katsuhiro Suzuki 1, Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Auto (72) Inventor Hideki Miyata 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Tomoaki Fukuhara 1-7-1 Yokoi, Shimada City, Shizuoka Prefecture Yazaki Keiki Co., Ltd.

Claims (4)

[Claims] 1. A main body including a temperature sensing part and a terminal connected to the temperature sensing part; a lead wire connected to the terminal; and a fitting part of at least the terminal and the lead wire fitted to the main body. And a cover covering the lead wire, wherein the main body has a wire fixing groove for fitting a lead wire in a head thereof, and the cover has a wire cover portion for covering the lead wire fitted in the wire fixing groove. A temperature sensor, wherein the head of the main body has an exposed surface exposed from the cover in a portion other than the portion covered with the wire cover portion. 2. The main body has a wire fixing groove inside and a wire cover fixing groove outside the wire fixing groove. The wire cover is fixed to the wire cover fixing groove in a dovetail shape to connect a lead wire. The temperature sensor according to claim 1, wherein the temperature sensor stops. 3. The temperature sensor according to claim 1, wherein said wire fixing groove has axial displacement preventing means for locally crushing a lead wire fitted in said wire fixing groove in a radial direction. 4. The temperature sensor according to claim 1, wherein said main body has a fitting groove of a fixture for fixing to a device on a side portion thereof.