JPH10232169A - Intake air temperature sensor - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To realize an intake air temperature sensor capable of reducing the number of parts and also reducing the number of steps for mounting on an internal combustion engine. A head of an intake air temperature sensor is formed into a shape that can be attached by a driver or the like, and is smaller than an inner diameter of a first hole of an attachment hole and larger than an inner diameter of a second hole. First
, A second disc-shaped portion smaller than the inner diameter of the second hole and larger than the inner diameter of the third hole, and a columnar portion smaller than the inner diameter of the third hole. Have. A thread is formed on the surface of the column. Conventionally, the mounting of the intake air temperature sensor 4 uses a mounting screw hole of the electronic component 1 provided on the intake pipe 8 to mount the electronic component 1 on the intake pipe 8. The screw hole is provided as a through-hole into the intake pipe so that the intake temperature sensor 4 can be inserted to a position where the intake temperature sensor 4 is exposed to the intake air 9, and the intake temperature sensor 4 is attached by screwing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an intake air temperature sensor for measuring the temperature of intake air flowing through an intake air passage of an internal combustion engine.

[0002]

2. Description of the Related Art A conventional intake air temperature sensor is a stand-alone type, as described in Japanese Patent Application Laid-Open No. 6-160204, for example, and a dedicated connector is integrated and attached to an intake system of an internal combustion engine. ing. Further, a structure for securely attaching the intake air temperature sensor to the intake system is described in JP-A-7-77461. According to Japanese Patent Application Laid-Open No. 7-77461, a cylindrical socket is formed on a structural member such as an intake manifold, and a temperature probe having a plastic shell is inserted into the socket. Is incorporated. These are disclosed in JP-A-6-16020.
No. 4 and Japanese Unexamined Patent Publication No. 7-77461 are all stand-alone types in which a connector and an intake air temperature detecting element are integrated.

Further, as disclosed in Japanese Patent Application Laid-Open No. Hei 8-21938, for example, a structure in which a temperature detecting element is integrated into a heating resistor type air flow measuring device for measuring an amount of air taken into an engine and a connector is shared has been devised. Has been put to practical use.

[0004]

By the way, in an engine room of an automobile using an electronically controlled fuel injection system, various sensors and control devices are narrowly arranged. Further, a wiring harness electrically connected to a sensor, a control device, a control unit for controlling the sensor, a control device, and the like is also complicated.

[0005] For this reason, from the viewpoint that maintenance and the like of equipment are extremely complicated, it is desired to reduce the number of parts by integrating a plurality of sensors and control equipment. For example, a structure in which the above-described heating resistor type air flow rate measuring device and the intake air temperature detecting element are integrated and a connector is shared is an example of a reduction in the number of parts, and the number of steps for assembling parts to a vehicle and the wiring harness are reduced. Simplification is possible.

However, in the above-described conventional technique, the number of parts cannot be further reduced. Therefore, there is a strong demand for further reduction in the number of parts, particularly for streamlining the method of mounting sensors and control devices and for sharing parts.

An object of the present invention is to realize an intake air temperature sensor capable of reducing the number of parts and reducing the number of steps for mounting the internal combustion engine.

[0008]

[Means for Solving the Problems]

(1) In order to achieve the above object, the present invention is configured as follows. That is, in the intake air temperature sensor that measures the intake air temperature supplied to the internal combustion engine, a temperature detecting element is embedded therein, and a screw thread that is screwed into a screw hole formed in a member of the internal combustion engine is formed on the surface thereof, The predetermined component is attached to the internal combustion engine member by being screwed into a screw hole formed in the internal combustion engine member through a through hole formed in the predetermined component.

[0009] The intake air temperature sensor is commonly used as a mounting member for mounting the predetermined component to a member of the internal combustion engine. This makes it possible to omit a mounting member that is required separately from the intake air temperature sensor, and to assemble the intake air temperature sensor to the internal combustion engine with the same man-hour as the number of man-hours for mounting the predetermined component to the internal combustion engine member. Becomes possible.

(2) Preferably, in the above (1),
A signal output unit that outputs a detection signal of the temperature detection element,
A signal input portion is disposed in the mounting hole of the predetermined component, and the predetermined component is mounted on a member of the internal combustion engine by the intake air temperature sensor. Is electrically connected to the signal input section.

Thus, the signal output section of the temperature detecting element and the signal input section of the predetermined component can be electrically connected at the same time when the predetermined component is attached to the member of the internal combustion engine.

(3) Preferably, in the above (2), the signal output section of the temperature detecting element is arranged substantially in a direction of insertion of the intake air temperature sensor into a screw hole of a member of the internal combustion engine. It has a shape that is parallel to the vertical plane.

According to this, if the signal input portion of the predetermined component is formed in a step parallel shape so as to face and contact the step parallel shape of the signal output portion of the temperature detecting element,
The connection between the signal input section of the predetermined component and the signal output section of the temperature detection element is ensured.

(4) An electronic component which is attached to an intake pipe member of an internal combustion engine and has a connector for inputting / outputting an electric signal. It has a plane made of a conductive member parallel to the step, and the conductive member parallel to the step is electrically connected to the terminal of the connector.

According to this, if the signal output portion of the temperature detecting element is formed in the step parallel shape so as to face and contact the step parallel shape of the signal input portion of the predetermined component, the predetermined level is obtained. The connection between the signal input part of the component and the signal output part of the temperature detecting element is ensured.

(5) Preferably, in the above (1), a signal output section for outputting a detection signal of the temperature detection element is provided, and the signal output section and the intake air temperature detection element are covered with an insulating material. Are connected by a lead wire provided with a.

Thus, a contact failure between the lead wires inside the intake air temperature sensor is reliably prevented.

(6) Preferably, in the above (2), the signal output portion of the temperature detecting element is formed with a conductive convex portion projecting opposite to the signal input portion of the predetermined component. ing.

Thus, the connection between the signal input section of the predetermined component and the signal output section of the temperature detecting element is ensured.

(7) Preferably, in the above (2), the signal output section of the temperature detecting element is a spring-like member which expands and contracts in opposition to the signal input section of the predetermined component.

Thus, the connection between the signal input section of the predetermined component and the signal output section of the temperature detecting element is ensured.

(8) Preferably, in the above (1), the intake air temperature sensor and the predetermined part are connected to each other by the intake air temperature sensor in a state where the predetermined part is attached to a member of the internal combustion engine. Is covered with a coating material for the purpose of preventing intrusion of moisture, oil and the like from the gap.

With the above-mentioned coating member, intrusion of moisture, oil and the like from the gap can be prevented.

(9) In the control system for an internal combustion engine, the intake air temperature sensor of the above (1) is attached to a member of the internal combustion engine via the above-mentioned predetermined component. The control of the internal combustion engine is performed using the output signal of the internal combustion engine.

[0025]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view showing a state in which an intake air temperature sensor 4 according to an embodiment of the present invention is mounted on an intake pipe 8 together with an electronic component 1, and FIG. The electronic component 1 has, for example, a signal processing circuit or the like of an air flow measuring device. In the electronic component 1, the connector 2 is integrally formed with a resin housing member. Inside the connector 2, an intake air temperature external output terminal 3 is provided in addition to an existing output terminal.

The intake temperature external output terminal 3 extends through the inside of the resin housing of the electronic component 1 to the inner peripheral surface of a mounting hole (through hole) 33 formed in the electronic component 1. The mounting hole 33 has a stepped parallel shape whose inner diameter decreases stepwise. That is, the mounting hole 33 has a first hole having a first inner diameter, a second hole having a second inner diameter smaller than the first inner diameter, and a third inner diameter smaller than the second inner diameter. And a third hole portion. The resin housing of the electronic component 1 is attached to the intake pipe 8 such that the side surface on which the third hole is formed faces the intake pipe 8 side.

The external output terminal 3 is divided into two terminal portions, and one terminal portion is formed in an annular shape having an inner diameter equivalent to the inner diameter of the second hole of the mounting hole 33. 33 is a plane substantially perpendicular to the central axis of
Are arranged in the holes. The other terminal portion of the external output terminal 3 is formed in an annular shape having an inner diameter equal to the inner diameter of the third hole of the mounting hole 33, and is substantially perpendicular to the center axis of the mounting hole 33. And disposed in the second hole. Therefore, one terminal portion and the other terminal portion of the external output terminal 3 are arranged on mutually parallel planes that are substantially perpendicular to the central axis of the mounting hole 33 and that are parallel to each other.

The intake air temperature sensor 4 is, as shown in FIG.
The head (the end opposite to the insertion end inserted into the screw hole of the member of the internal combustion engine) is formed into a screw head shape that can be attached by a general-purpose tool such as a driver or by hand. In the intake air temperature sensor 4, a thermistor 5 is used as a temperature detecting element, and a lead wire 6 of the thermistor 5 and an intake air temperature output terminal 7 are connected by welding, soldering, caulking, or the like, and are formed into a screw shape. It is formed by integral molding.

The intake air temperature sensor 4 has a first disc-shaped portion (flange-shaped portion) which is smaller than the inside diameter of the first hole of the mounting hole 33 but larger than the inside diameter of the second hole. ) 4a (shown in FIG. 2), which is formed adjacent to the first disk-shaped portion and is smaller than the inner diameter of the second hole of the mounting hole 33, but is smaller than the inner diameter of the third hole. A large second disk-shaped portion (flange-shaped portion) 4b (shown in FIG. 2). That is, the first disk upper part 4
a and the upper portion 4b of the second disk,
It is formed so as to be parallel to a substantially vertical plane.

The intake air temperature sensor 4 has a columnar portion adjacent to the second disk-shaped portion and smaller than the inner diameter of the third hole of the mounting hole 33. Spiral mountains,
That is, a screw thread that is screwed with the screw thread of the mounting screw hole formed in the intake pipe 8 is formed. The intake temperature output terminal 7 is divided into two parts as shown in FIG. 7 or FIG. 8, and one part of the output terminal 7 has an inner diameter equivalent to that of the second disk-shaped portion 4b. An annular terminal having
The lower surface of the first disk-shaped part 4a, that is, the second disk-shaped part 4
It is arranged on the b-side surface.

The other portion of the output terminal 7 is an annular terminal having an inner diameter equivalent to that of the third disk-shaped portion 4b, and is a lower surface of the second disk-shaped portion 4b, that is, a column. It is arranged on the part side surface. Then, one part of the output terminal 7 is connected to one of the leads 6 of the thermistor 5, and the other part of the output terminal 7 is connected to the other of the leads 6 of the thermistor 5.

Conventionally, the intake air temperature sensor 4 is mounted using a mounting screw hole of the electronic component 1 provided on the intake pipe 8 for mounting the electronic component 1 on the intake pipe 8. The screw hole is formed as a through screw hole into the intake pipe so that the intake temperature sensor 4 can be inserted to a position where the intake temperature sensor 4 is exposed to the intake air 9, and the intake temperature sensor 4 is attached by screwing.

As a result, the electronic component 1 can be simultaneously attached to the intake pipe 8 by the intake temperature sensor 4, and the intake temperature output terminal 7 is brought into contact with the intake temperature external output terminal 3 to obtain electrical continuity. The intake air temperature signal can be output from the connector 2 of the electronic component 1 to the outside.

With the configuration of the intake air temperature sensor 4 described above,
A screw for attaching the electronic component 1 to the intake pipe 8 becomes unnecessary, and an existing screw hole formed in the intake pipe 8 can be used. Therefore, it is necessary to separately secure a special arrangement area for the intake air temperature sensor. And the number of parts can be reduced. In addition, the intake air temperature sensor 4 can be incorporated into the vehicle in the same man-hour as the assembly time required for the electronic component 1, and the connector dedicated to the intake air temperature sensor required so far can be eliminated. There is a merit that can be simplified.

Also, the connection from the thermistor 5 to the intake air temperature external output terminal 3 does not require the conventional welding and bonding techniques of nickel and aluminum wires, so that productivity and connection reliability can be improved.

FIG. 3 is a front view showing an example of mounting the intake air temperature sensor 4 and the heating resistor type air flow measuring device.
FIG. 4 is a sectional view of FIG. 3. The heating resistor type air flow measuring device includes an intake pipe 8 and a sub air passage 1 through which a part thereof flows.
The amount of intake air supplied to the engine through zero is measured.
The auxiliary air passage 10 is integrated with the drive circuit module 11,
It is inserted into the intake pipe 8 and used. A heating resistor 12 for measuring the flow rate of the intake air 9 and a temperature sensitive resistor 13 for compensating the intake air temperature are provided in the sub air passage 10.

The heating resistor 12 and the temperature-sensitive resistor 13 are electrically connected to the drive circuit board 15 by the support pins 14 to form the drive circuit module 11. The drive circuit module 11 is provided with an intake air temperature external output terminal 3, and the drive circuit module 11 is fastened to the intake pipe 8 by the intake air temperature sensor 4, so that the air flow signal and the intake air temperature are transmitted from the connector 2 of the heating resistor type air flow measuring device. A signal can be output, and a heating resistor type air flow measuring device integrated with an intake temperature sensor having a simple structure can be realized.

FIG. 5 is a diagram for explaining an operation of attaching the electronic component 1 to the intake pipe 8 by the intake air temperature sensor 4. As described above, the intake air temperature external output terminal 3 and the intake air temperature output terminal 7 are arranged stepwise parallel to a plane perpendicular to the screwing direction of the intake air temperature sensor 4. With this configuration, when the intake air temperature sensor 4 and the electronic component 1 are fastened together, the intake air temperature external output terminal 3 and the intake air temperature output terminal 7 can be brought into contact with each other in the screwing direction of the intake air temperature sensor 4, so that a larger mechanical and An electric coupling force can be obtained.

FIG. 6 is a view for explaining the mounting of the electronic component 1 on the intake pipe 8 when the intake air temperature sensor 4 is not required in the engine control system of the automobile. Electronic component 1
Usually has a configuration that can be fixed with screws 16 used. With this configuration, it is possible to easily cope with the necessity of the intake air temperature sensor 4 and the necessity thereof. Further, parts such as the housing of the electronic part 1 can be shared in both cases where the intake air temperature sensor 4 is necessary and cases where it is not necessary.

FIG. 7 is a diagram showing an example of the shape of the thermistor 5, the lead wire 6, and the intake air temperature output terminal 7 of the intake air temperature sensor 4. In FIG. 7, the lead wire 6 of the thermistor 5 is wired so as to pass through the inside of the annular intake air temperature output terminal 7 in order to form the intake air temperature sensor 4 into a small size. For this reason, the surface of the lead wire 6 is coated with a vinyl tube 17 in order to prevent a short circuit between the intake air temperature output terminal 7 and the lead wire 6 or a short circuit between the lead wires 6 at the time of resin integral molding.

FIG. 8 is a diagram showing another example of the shape of the intake air temperature output terminal 7 of the intake air temperature sensor 4. 8, the intake air temperature output terminal 7 of the intake air temperature sensor 4 is formed in the shape of a spring (spring washer) that expands and contracts in opposition to the external intake air temperature output terminal 3, and the pressure applied to the external intake air temperature output terminal 3 is reduced. The structure is strengthened and the electrical connection is reliably performed.

Since a slit for forming the intake air temperature output terminal 7 in a spring shape is provided, after the lead wire 6 is connected to the intake air temperature output terminal 7, the lead wire 6 is connected to the intake air temperature output terminal via the slit. It is possible to pass through the terminal 7, and there is an advantage that the connection between the lead wire 6 and the intake air temperature output terminal 7 is easy and the degree of freedom in productivity is increased.

Further, the intake air temperature output terminal 7 may be formed with a conductive protrusion protruding opposite to the intake air temperature external output terminal 3. Even with this configuration, the crimping force between the intake air temperature output terminal 7 and the external intake air temperature output terminal 3 is increased, and the electrical connection is reliably performed.

FIG. 9 is a sectional view showing another example of a state in which the intake air temperature sensor 4 is attached to the intake pipe 8. In FIG. 9, after the intake air temperature sensor 4 and the electronic component 1 are fastened together, a screw head is provided to prevent poor contact due to intrusion of moisture or oil into the gap or contact portion between the terminals 3 and 7. Alternatively, an epoxy resin adhesive (coating material) 18 or the like is applied around the periphery. With this configuration, the seal from the screw portion to the inside of the intake pipe can be reliably performed, and the loosening of the screw can be prevented.

FIG. 10 is a diagram showing an example in which the intake air temperature sensor 4 of the present invention is applied to a control system for an electronic fuel injection type internal combustion engine. In FIG. 10, the intake air 9 sucked from the air cleaner 19 is supplied to a body 20, an intake duct 21, and a throttle body 2 of a heating resistor type air flow measuring device.
The fuel is sucked into an engine cylinder 25 through an intake manifold 24 having an injector 23 to which fuel 2 and fuel are supplied. On the other hand, the gas 2 generated in the engine cylinder 25
6 is discharged through the exhaust manifold 27.

The air flow signal output from the drive circuit module 11 of the heating resistor type air flow measuring device, the intake air temperature signal output from the intake air temperature sensor 4, the throttle valve angle signal output from the throttle angle sensor 28, and the exhaust manifold 27 The control unit 31 that inputs these signals, such as the oxygen concentration signal output from the oximeter 29 and the engine rotation speed signal output from the engine tachometer 30, sequentially calculates these signals and optimizes them. The fuel injection amount and the idle air control valve opening are obtained, and the injector 23 and the idle control valve 32 are controlled using the calculated values.

In the control system for an internal combustion engine shown in FIG. 10, since the above-described intake air temperature sensor 4 is used, the number of parts can be reduced as a whole control system.

In the example shown in FIG. 1 described above, an example is shown in which the intake air temperature sensor 45 of the present invention is used in an air flow rate measuring device. It can also be applied to temperature correction of a throttle sensor and a pressure sensor.

[0049]

Since the present invention is configured as described above, it has the following effects. The above-described configuration of the intake air temperature sensor eliminates the need for screws for mounting electronic components to the intake pipe and the like, and allows the use of existing screw holes formed in the intake pipe and the like. The number of components can be reduced without having to secure a separate arrangement area.

Also, the intake air temperature sensor can be incorporated into the vehicle in the same number of man-hours required for assembling the electronic parts, and a connector dedicated to the intake air temperature sensor required so far can be eliminated. There is a merit that can be simplified.

Also, the integration of the seed electronic components and the sensors can be achieved, and the system cost of the intake system can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a state in which an intake air temperature sensor according to an embodiment of the present invention is attached to an intake pipe together with electronic components.

FIG. 2 is an external view of an intake air temperature sensor according to an embodiment of the present invention.

FIG. 3 is a front view of a mounting example of an intake air temperature sensor and a heating resistor type air flow measuring device.

FIG. 4 is a cross-sectional view of an intake air temperature sensor, a heating resistor type air flow measurement device, and an example of installation.

FIG. 5 is a diagram illustrating an operation of attaching an electronic component to an intake pipe by an intake air temperature sensor.

FIG. 6 is a diagram for explaining attachment of an electronic component to the intake pipe 8 when an intake temperature sensor is not required in the control system.

FIG. 7 is a view showing an example of the shapes of a thermistor, a lead wire, and an intake air temperature output terminal of the intake air temperature sensor.

FIG. 8 is a diagram showing another example of the shapes of the thermistor, lead wire, and intake air temperature output terminal of the intake air temperature sensor.

FIG. 9 is a cross-sectional view showing another example of a state where the intake air temperature sensor is attached to the intake pipe.

FIG. 10 is a diagram showing an example in which the intake air temperature sensor of the present invention is applied to a control system of an internal combustion engine of an electronic fuel injection system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic component 2 Connector 3 Intake temperature external output terminal 4 Intake temperature sensor 4a, 4b Disc-shaped part (flange part) 5 Thermistor 6 Lead wire 7 Intake temperature output terminal 8 Intake pipe 9 Intake air 10 Sub air passage 11 Drive circuit Module 12 Heating resistor 13 Temperature sensing resistor pair 14 Support pin 15 Drive circuit board 16 Screw 17 Vinyl tube 18 Epoxy adhesive 19 Air cleaner 20 Body 21 Suction duct 22 Throttle body 23 Injector 24 Intake manifold 25 Engine cylinder 26 Gas 27 Exhaust manifold 28 Throttle angle sensor 29 Oxygen meter 30 Tachometer 31 Control unit 32 Idle air control valve 33 Mounting hole

Claims (9)

[Claims] 1. An intake air temperature sensor for measuring an intake air temperature supplied to an internal combustion engine, wherein a temperature detecting element is embedded therein, and a screw thread screwed into a screw hole formed in a member of the internal combustion engine is provided on the surface thereof. The predetermined component is attached to the internal combustion engine member by being screwed into a screw hole formed in the internal combustion engine member through a formed through hole formed in the predetermined component. Intake air temperature sensor. 2. The intake air temperature sensor according to claim 1, wherein
A signal output unit that outputs a detection signal of the temperature detection element,
A signal input portion is arranged in a mounting hole of the predetermined component, and the predetermined component is mounted on a member of the internal combustion engine by the intake air temperature sensor. An air temperature sensor is electrically connected to the signal input section of 3. The intake air temperature sensor according to claim 2, wherein
The signal output section of the temperature detection element has a shape that is stepwise parallel to a plane substantially perpendicular to an insertion direction in which the intake air temperature sensor is inserted into a screw hole of the member of the internal combustion engine. Sensor. 4. An internal combustion engine mounted on an intake pipe member,
An electronic component having a connector for inputting and outputting an electrical signal, the electronic component having a through-hole, having a plane formed of a conductive member parallel to the center axis of the through-hole, and having a plane parallel to the step. An electronic component, wherein the conductive member is electrically connected to the terminal of the connector. 5. The intake air temperature sensor according to claim 1, wherein
A signal output section for outputting a detection signal of the temperature detection element, wherein the signal output section and the intake air temperature detection element are connected by a lead wire coated with an insulating material; Temperature sensor. 6. The intake air temperature sensor according to claim 2, wherein
An intake air temperature sensor, characterized in that a signal output portion of the temperature detection element is formed with a conductive protrusion projecting opposite to a signal input portion of the predetermined component. 7. The intake air temperature sensor according to claim 2, wherein
An intake air temperature sensor, wherein the signal output section of the temperature detecting element is a spring-like member that expands and contracts in opposition to the signal input section of the predetermined component. 8. The intake air temperature sensor according to claim 1, wherein
With the intake air temperature sensor, a gap between the intake air temperature sensor and the predetermined component in a state where the predetermined component is attached to a member of the internal combustion engine prevents entry of moisture, oil, and the like from the gap. An intake air temperature sensor covered with a coating material for the purpose. 9. A control system for an internal combustion engine, wherein the intake air temperature sensor according to claim 1 is mounted on a member of the internal combustion engine via the predetermined component, and an output signal from the intake air temperature sensor in the mounted state. A control system for an internal combustion engine, wherein the control of the internal combustion engine is performed by using a computer.