JP2001214776A - Automotive control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount a pressure sensor on the inner part of the sealed case of an automotive control device without loosing the function of pressure measurement. SOLUTION: An engine control circuit board 15 and the pressure sensor 20 are housed in one control unit case (for example, ECU case) 11. The ECU case 11 (or the cover thereof) comprises a hole 18 for guiding a pressure to be detected. The pressure sensor 20 has a sensor case 22 for housing a gauge chip 21, and installed in the ECU case 11 together with the sensor case 22. The gauge chip 21 is opposed to the hole 18. The sensor case 22 is adhered to the inside of the ECU case 11 or the cover thereof so as to interrupt the hole 18 from the inner part of the ECU case 11. A cover 14 is also adhered to the ECU case.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vehicle having a pressure sensor (for example, a device for controlling an engine or a throttle).

[0002]

2. Description of the Related Art A conventional electronic control unit for an automobile engine (here, an engine control unit is taken as an example,
The engine control device may be abbreviated as ECU) in general. On the other hand, pressure sensors for detecting atmospheric pressure and the like are mounted outside the vehicle compartment, such as in an engine room. Therefore, the ECU and the pressure sensor are connected via a cable (wire harness).

[0003] In addition to the atmospheric pressure measurement, for example, as disclosed in Japanese Patent Application Laid-Open No. Hei 9-151807, a pressure sensor is used to control the exhaust gas recirculation (exhaust gas recirculation: EGR) when adjusting the electronic negative pressure. Some also use negative pressure measurement.

However, the EGR device is replaced with a negative pressure drive type, for example, as disclosed in Japanese Patent Laid-Open No. Hei 10-82349.
The motor type is spreading, and in this case, the negative pressure measurement becomes unnecessary. However, atmospheric pressure measurement is necessary for various control purposes in the ECU, and the atmospheric pressure sensor itself exists.

When a pressure sensor is used for measuring atmospheric pressure, if the wire harness can be reduced, the weight of the vehicle can be reduced,
The installation cost to the vehicle can be reduced. for that purpose,
It is also conceivable to incorporate a pressure sensor in the ECU.

When the ECU is installed in the vehicle interior, the inside of the ECU case is open to the atmospheric pressure.
When incorporating the atmospheric pressure sensor inside the above case,
There is no need to provide a pressure introducing section.

[0007] Recently, an ECU arranged in an engine room has been put to practical use in order to shorten the wire harness. In this case, in order to protect the circuit board in the ECU case from water, dust and the like outside the ECU, the case needs to have a sealed structure.

When a pressure sensor for measuring the atmospheric pressure is installed in such an ECU case, a membrane through which only gas molecules can pass is attached to a pressure introducing portion such as a cover, so that water or the like enters from outside into the ECU. There is also proposed a technique of detecting atmospheric pressure by introducing the atmosphere into a case while preventing the pressure.

However, it is necessary to devise a bonding method so that water or the like does not enter from the bonding portion of the film, and the number of parts and the number of steps for bonding increase, thereby increasing the cost.

[0010] In the prior art, there is also known a technology in which an atmospheric pressure sensor is provided inside an ECU case and an intake pressure sensor is provided therein.

For example, Japanese Patent Application Laid-Open No. 8-28315 discloses a method in which an intake pressure sensor is built in an ECU installed in an engine room, and this pressure sensor and an intake pipe are connected by a pressure introducing hose. However, a closed structure of the case for specific realization is not disclosed.

In Japanese Patent Application Laid-Open No. 11-218041, a circuit board of the ECU is provided on the inner surface of the control board and the pressure sensor is mounted on the outer surface in order to integrate the pressure sensor for measuring the intake pipe pressure with the ECU. In addition, there has been proposed a configuration in which a circuit board and a pressure sensor are disposed in a partitioned storage section by partitioning the inside of an ECU case.

[0013] Recently, even in a control device mounted in a vehicle cabin, when water enters the vehicle cabin, a circuit in the control device is short-circuited to prevent a power window or the like from operating, and a countermeasure is taken to use a sealed structure. There is also.

In some cases, a pressure sensor is incorporated as a component into an actuator (electronically controlled throttle device) such as a throttle chamber. Even in such a case, it is necessary to eliminate the cable and reduce the number of assembling steps by housing the pressure sensor in the case of the actuator control board.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a control unit case such as an ECU or a throttle device having a closed structure suitable for installation in an engine room. The pressure sensor can be mounted together with the circuit board by a different rational case structure, making it more compact than before, and also ensuring a simple accommodating space without complicating the compartment space inside the case and consolidating components. An object of the present invention is to provide a control device for a vehicle which can be manufactured at low cost, can be easily assembled, and can rationalize an installation space.

[0016]

The present invention is configured as follows to achieve the above object.

Basically, a circuit board for engine control and a pressure sensor are housed in one control unit case (for example, an ECU case).

In the first invention, on the premise of this, the control unit case or its cover is provided with a hole for guiding the pressure to be detected. The pressure sensor has a sensor case accommodating the gauge, and is housed in the control unit case together with the sensor case. in this case,
The gauge faces the hole. On the other hand, the sensor case is adhered to the inside of the control unit case or its cover so as to block between the hole and the inside of the control unit case. The cover is also adhered to the control unit case.

According to a second aspect of the present invention, instead of the gauge of the pressure sensor facing the hole provided in the control unit case or its cover as in the first aspect, a pressure introducing portion provided in the pressure sensor is provided in the hole. Let it through. The sensor case of the pressure sensor is adhered to the inside of the control unit case or its cover so as to close the gap between the inner periphery of the hole and the outer periphery of the pressure introducing portion. The cover is adhered to the control unit case.

The details and advantages of the structure of the present invention will be described in detail in the embodiments of the present invention.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments shown in the drawings.

FIG. 1 is a longitudinal sectional view of a vehicle ECU (engine control device) according to a first embodiment of the present invention, and FIG. 2 is a pressure sensor (here, an atmospheric pressure sensor) incorporated in the ECU. FIG. 3 is a schematic sectional view showing a connection relationship between a circuit board of the ECU and various sensors.

As shown in FIG. 1, a control unit case 11 (hereinafter, also referred to as an ECU case in this embodiment) 11 of the ECU 10 is box-shaped, and is integrally formed with a connector portion 12 by a synthetic resin.

The ECU case 11 houses a circuit board 15 for engine control and a pressure sensor 20. The opening of the case 11 is covered with a lid-like cover 14, and the cover 14 is bonded to the case 11.

As shown in FIG. 2, the pressure sensor 20 includes a sensor case 22, a chip 21 including electronic circuits such as a gauge serving as a pressure detection unit and an amplification adjustment circuit, and a glass die 2.
8, a lead frame 23, a base frame 29, and the like.

The chip 21 is accommodated in a pocket (accommodating portion) 24 of the sensor case 22 and its base frame 29
It is adhered on the upper side with an adhesive 27 via a glass die 28. As the adhesive 27, it is desirable to use a soft adhesive such as a silicone-based adhesive in order to reduce stress caused by a difference in thermal expansion coefficient between the glass die 28, the base frame 29, and the sensor case 22.
The chip 21 is anodically bonded on a glass die 28.

The gauge portion (not shown) formed on the chip 21 has a diaphragm structure,
The pressure measured by deflects the diaphragm. A bridge is formed in the gauge by diffusion resistance, and an electric signal is output due to the imbalance of the bridge due to deformation. The desired output is obtained by passing this signal through an amplification adjustment circuit.

The sensor case 22 is provided with a plurality of lead frames 23 for supplying a power supply voltage for operating the chip 21 from the outside and for guiding a sensor output signal (electric signal) to the outside. These lead frames 2
3 and the base frame 29 are buried in the resin mold at the same time when the sensor case 22 is molded (insert molding), and a part of the lead frame 23 is exposed on the surface of the sensor case 22. As shown in FIG. 1, connection with the circuit board 15 via the wires 16 is enabled.

The pocket 24 has a concave shape with an open surface, and a gel 24 'is sealed inside the pocket 24 through the opening to protect the sensor. This gel 24 'contains water, gasoline,
In order to protect the chip 21 from acid or the like, it is necessary to use a material having excellent chemical resistance, and is a material capable of transmitting an external pressure to a pressure detection unit on the chip 21. It is a fluorosilicone gel.

The sensor case 22 has a groove 26 for bonding to the ECU case 11. The groove 26 is an annular groove formed in the circumferential direction of the sensor case 22. On the other hand, as shown in FIG. 1, an adhesive groove (annular groove) 13 is also formed at the pressure sensor installation location on the inner surface of the ECU case 11, and the grooves of these annular grooves 13, 26 and the groove walls are formed. The pressure sensor 20 is adhered to the inside of the ECU case 11 via an adhesive injected into the groove while engaging the concave and convex.

The location of the pressure sensor in the ECU case 11 is set near one side of the case 11.
A hole 18 for guiding pressure (here, atmospheric pressure) is provided at a position corresponding to the sensor installation location at the bottom of the sensor.

The pressure sensor chip 21 (gauge) faces the hole 18, and the sensor case 20 blocks the space between the hole 18 and the inside of the ECU case 11 so that the ECU case 1
1 is adhered to the inside of the bottom.

Inside the ECU case 11, a pressure sensor 21 and a circuit board 15 for engine control are disposed close to each other on the bottom surface thereof.

FIG. 3 shows a circuit board 15 and a pressure sensor 20 housed in the ECU case 11, various sensors (for example, a water temperature sensor, an engine speed sensor, an air flow sensor, etc.) 68 and various actuators (for example, an injector). Etc.).

The area surrounded by the dashed line corresponds to the circuit board 15 (the circuit board 15 is actually a square), and the area surrounded by the broken line is the area of the ECU unit 10.

The circuit board 15 includes a central processing unit (CP)
U) 61, a read-only storage device (ROM) 62, a nonvolatile storage device (PROM) 63, a read / write storage device (RAM) 64, and an input / output controller (I / O) 65. Connected at 66. The circuit board 15 includes an input signal processing circuit 67 and an output drive circuit 69. Reference numeral 151 in FIG. 1 unifies the various devices, signal processing circuits, and output drive circuits that constitute the ECU.

Signals from various sensors 68 including the pressure sensor 20 are input to an I / O
Input to O65.

The CPU 61 performs calculations based on a predetermined control program stored in the ROM 62 or PROM 63 in advance. From the calculation result, a control signal is output from the I / O 65 to each actuator 70 via the output drive circuit 69.

Various sensors (external sensors) 68 other than the pressure sensor 20 and an input signal processing circuit 67 in the ECU
It is electrically connected via a waterproof connector 12 provided on the U case 11. Similarly, each actuator 70 and the output drive circuit 69 are connected via the waterproof connector 12.
154 is a terminal of the connector 12, which is a signal input terminal,
It consists of a number of various terminals such as an output terminal and a power supply terminal.

These connector terminals 154 are connected to corresponding pads 153 provided on circuit board 15 and aluminum wires 17.
Connected through.

The pad 152 corresponding to the pressure sensor on the circuit board 15 is arranged on one side near the installation location of the pressure sensor 20, and is connected to the lead frame 23 of the pressure sensor 20 via the wire 16.

According to the present embodiment, the following operations and effects are obtained.

Gauge of pressure sensor 20 (chip 21)
Faces the pressure introducing hole 18 provided in the ECU case 11, so that the atmospheric pressure can be measured and the sensor case 22 can be measured.
Is bonded to the inside of the ECU case 11 so as to block between the pressure introducing hole 18 and the inside of the ECU case 11, and the cover 14 is also bonded to the ECU case 11.
Even if the atmospheric pressure sensor 20 is provided inside the case 11, the airtightness inside the ECU case can be maintained.

Therefore, the E having the pressure sensor 20 therein
Even if the CU 10 is installed in the engine room, the control circuit and the like in the ECU case 11 can be protected from water, dust and the like outside the ECU case.

When the ECU 10 is mounted in an engine room, water or the like is applied to the outside of the ECU, and there is a possibility that water may enter the pressure detecting section of the pressure sensor 20 from the pressure introducing section 18. If this water remains without being discharged from the pressure introduction unit, it may freeze as it is and destroy the pressure detection unit. Therefore, the opening of the pressure introducing portion is directed downward, so that water does not easily reach the pressure introducing portion, and the intruded water is easily discharged. This can prevent the pressure sensor from icing.

By mounting the pressure sensor 20 in the ECU case 11, the sensor 20 and the engine control circuit board 1 are mounted.
5 and the signal processing circuit and its protection circuit are mounted on the circuit board 15, so that the cost can be reduced and the radio noise resistance can be improved. Moreover, by reducing the wire harness, it is possible to reduce the cost of the harness and reduce the weight of the vehicle.

Since the sensor case 22 of the pressure sensor 20 functions to seal the ECU case 11 inside the case, the inside of the ECU case 11 partitions the pressure sensor accommodating portion and the circuit board accommodating portion for airtightness. This eliminates the necessity, and as a result, the entire ECU 10 can have a very simple shape and can be reduced in size, and furthermore, simplification and cost reduction of assembly and installation can be realized.

Further, the shape of the pressure sensor 20 can be reduced by transferring part or all of the signal processing circuit to the circuit board 15 on the ECU side.
The installation space of the ECU case 11 for the pressure sensor 20 is reduced, which contributes to downsizing of the ECU.

The ECU 10 writes a coefficient for correcting the output characteristic of the pressure sensor 20 in the storage device of the circuit board 15 and has an arithmetic means for correcting the output of the pressure sensor using the correction coefficient. .

That is, the circuit board 15 includes the CPU 61,
Although it is composed of a ROM 62, a RAM 63, a PROM 63, an I / O 65, etc., the characteristics of the pressure sensor are measured in advance, and a correction coefficient obtained from the characteristics is stored in the PROM 63.
And the like, and the CPU 61 performs an operation for correcting the characteristics.

In this way, since the storage device for correcting the output of the pressure sensor can use the storage device of the ECU circuit board 15, the cost can be reduced and the pressure sensor and the ECU can be downsized.

The pressure sensor 20 has manufacturing variations,
It is necessary to adjust the characteristics of each sensor individually. Pressure sensor 2
Before storing the 0 in the ECU 10, or after storing and bonding, the characteristics are measured, the correction coefficient is determined, and then written into a storage device such as the PROM 63 on a control device board having an arithmetic function.

At the time of actual operation of the control device 10, a correction operation is performed by the operation device of the circuit board.

FIG. 4 is a longitudinal sectional view of an engine control unit (ECU) 30 according to a second embodiment of the present invention, in which the same reference numerals as those in the first embodiment denote the same elements (FIG. 5 and subsequent figures). Similar).

The difference between this embodiment and the first embodiment is that first, the ECU case 11 is constituted by a base substrate (also serving as a heat sink) 31 made of aluminum or the like and a side frame 32 made of synthetic resin. It is in the point which did.
The side frame 32 and the base substrate 31 are integrated by so-called insert molding, in which the base substrate 31 is simultaneously set in a mold at the time of resin molding of the side frame 32.

The pressure introducing hole 33 (corresponding to the pressure introducing hole 18 in the first embodiment) is formed in a side frame (side surface) 32 of the ECU case 11. This pressure introduction hole 33
Is formed by projecting a part 32 ′ of the side frame 32 inside the ECU case 11, and a pressure sensor installation portion (adhesion portion) 34 similar to the first embodiment is formed in the side frame extension portion 32 ′. Things.

According to the present embodiment, the following advantages can be obtained in addition to the same effects as those of the first embodiment.

In order to enhance the heat dissipation of the circuit board 15, the ECU case 11 may be formed of aluminum as described above, and the frame side may be formed of synthetic resin to provide a connector. It is. In this case, the pressure sensor 2 is made of synthetic resin which is easier to process than aluminum.
By forming the zero installation portion 34 and the pressure introduction portion 33, it is possible to reduce the processing cost.

FIG. 5 is a longitudinal sectional view according to a third embodiment of the present invention.

The difference between this embodiment and the first and second embodiments is that a pressure introducing portion (hole) 45 is provided in the cover 42 of the ECU case 11 and the pressure sensor 20 is provided with its gauge portion (chip 21). The cylindrical part 4 forming the hole 45 facing the hole 45
The point is that the sensor case 22 is bonded to the tip of 5 '. Even in this case, the sensor case 22 causes the pressure introducing section 4
5 and the internal space of the ECU case 11 can be blocked. The tube portion 45 ′ extends toward the inside of the cover 42.

In this embodiment, the pressure sensor 20 is
After this, the cover 42 is bonded to the case 11 at the bonding portion 19.

With the above configuration, the same effects as those of the first aspect can be obtained.

Further, even in a conventional ECU having no built-in pressure sensor, the pressure sensor can be built in relatively easily without redesigning the ECU case 11 (by modifying only the cover side). Further, it is possible to select the built-in or non-built-in pressure sensor while standardizing the ECU case 11 side, which is expensive to manufacture, as one type.

FIG. 6 is a longitudinal sectional view according to a fourth embodiment of the present invention.

The difference between the present embodiment and the first embodiment is that a waterproof film 51 through which only gas molecules permeates is attached to the opening of the pressure introducing portion (hole) 18.

When the ECU 10 is mounted in an engine room, dust, water and the like are applied to the control device. Therefore, E
In the case where there is no flexibility in the mounting method of the CU, depending on the mounting method, water that has entered the pressure detecting unit of the pressure sensor from the pressure introducing unit remains without being discharged from the pressure introducing unit.
If it freezes as it is, the pressure detector may be destroyed. In this embodiment, such a problem can be prevented.

In the above description, the control apparatus for controlling the engine of an automobile, which houses the atmospheric pressure sensor, has been described. The present invention is not limited to this category. For example, (1) The pressure in the intake manifold is measured by connecting the pressure introducing portion 18 of the control device to an intake pipe (intake manifold) with a hose or the like.

(2) In a throttle actuator for controlling the opening degree of a throttle valve such as a throttle chamber, various applications are possible, such as housing a pressure sensor in a case of a control substrate.

FIG. 7 shows an application example (fifth embodiment).
The difference from the embodiment of FIG. 1 is that a connecting portion 71 of a hose 70 communicating with the intake pipe is provided in the ECU case 11. The hose connection part 71 is formed around the hole 18 serving as a pressure introduction part.

FIG. 8 is a longitudinal sectional view according to a sixth embodiment of the present invention.

Also in this embodiment, the circuit board 15 of the ECU 10 and the pressure sensor 20 are housed in the ECU case 11. The pressure sensor 20 has a cylindrical portion 81 serving as a pressure introducing portion formed in the sensor case 80 itself, and a gauge housing portion 8 therein.
Form 2

A hole 82 is provided in the ECU case 11 (or its cover), and the pressure introducing portion 81 is passed through the hole 82. The sensor case 80 is adhered to the ECU case 11 so as to close a gap between the inner periphery of the hole 82 and the outer periphery of the pressure introducing part 81. Otherwise, the configuration similar to that of the above-described embodiment is adopted, and the cover 14 is also adhered to the case 11.

In this embodiment, the same effects as those of the above-described embodiments can be obtained.

[0074]

As described above, according to the present invention, a circuit board having a rational case structure different from the conventional one is provided in a control unit case such as an ECU or a throttle device having a closed structure suitable for being installed in an engine room. A pressure sensor can be installed inside the case, making it more compact than before, and without complicating the compartments in the case, ensuring a simple storage space, consolidating components, reducing costs, and simplifying assembly. Thus, it is possible to provide a control device for a vehicle, which can streamline the installation space.

[Brief description of the drawings]

FIG. 1 is a vehicle ECU according to a first embodiment of the present invention.
FIG. 3 is a vertical cross-sectional view of (engine control device).

FIG. 2 is a vertical cross-sectional view showing a package of a pressure sensor (here, an atmospheric pressure sensor is exemplified) housed in the ECU as a single item.

FIG. 3 is a block circuit diagram showing a configuration of an ECU.

FIG. 4 is a longitudinal sectional view according to a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view according to a third embodiment of the present invention.

FIG. 6 is a longitudinal sectional view according to a fourth embodiment of the present invention.

FIG. 7 is a longitudinal sectional view according to a fifth embodiment of the present invention.

FIG. 8 is a longitudinal sectional view according to a sixth embodiment of the present invention.

[Explanation of symbols]

10: engine control device, 11: ECU case, 12:
Waterproof connector, 13: pressure sensor bonding part (installation part), 1
4 ... Cover, 15 ... Circuit board, 18 ... Pressure introduction part (hole), 20 ... Pressure sensor, 21 ... Chip (pressure detection gauge and electronic circuit), 22 ... Sensor case, 24 ... Gauge chip accommodating part (pocket), 26: adhesive groove, 51: waterproof membrane.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Miya ▲ saki ▼ Atsushi 2520 Oji Takaba, Hitachinaka City, Ibaraki Prefecture Within the Hitachi, Ltd.Automotive Equipment Group (72) Inventor Shoji Sasaki 2520 Oaza Takaba, Hitachinaka City, Ibaraki Prefecture Address Co., Ltd.Hitachi, Ltd.Automotive Equipment Group (72) Inventor Masahiro Zaitsu 2477 Takaba, Hitachinaka-shi, Ibaraki Pref.Hitachi Car Engineering Co., Ltd. (72) Inventor Mitsuru Watanabe 2520 Takada, Oita-shi, Hitachinaka-shi, Ibaraki Co., Ltd. (72) Inventor Masahiko Asano 2477 Takaba, Hitachinaka City, Ibaraki Pref. Hitachi Car Engineering Co., Ltd.

Claims (7)

[Claims] 1. A circuit board for controlling a vehicle and a pressure sensor are housed in one case (hereinafter, this case is referred to as a "control unit case"), and the control unit case or its cover is to be detected. A hole for guiding pressure is provided, wherein the pressure sensor has a sensor case for accommodating the gauge, wherein the gauge faces the hole, and the sensor case is provided between the hole and the inside of the control unit case. A control device for a vehicle, wherein the control unit case or the cover is adhered to the inside of the control unit case so as to block a gap therebetween, and the cover is adhered to the control unit case. 2. A control circuit board for a vehicle and a pressure sensor are housed in a control unit case, wherein the pressure sensor has a sensor case provided with a pressure introducing portion and a gauge housing portion, and the control unit case or a control unit case thereof. The cover is provided with a hole, the pressure introduction portion is passed through the hole, and the sensor case is configured such that the control unit case closes a gap between an inner periphery of the hole and an outer periphery of the pressure introduction portion. Alternatively, the cover is bonded to the inside of the cover, and the cover is bonded to the control unit case. 3. The vehicle control device according to claim 1, wherein a part or all of the signal processing circuit of the pressure sensor is transferred to a circuit board for vehicle control. 4. The vehicle control device according to claim 1, wherein said hole is formed in a side surface of said control unit case. 5. A control device for an automobile, wherein the hole according to claim 1 or the pressure introducing portion according to claim 2 is provided with a membrane through which only gas molecules pass. 6. The circuit board according to claim 1, further comprising: a storage medium for storing a correction coefficient relating to an output characteristic of the pressure sensor; and a calculation unit for correcting an output of the pressure sensor. 2. The control device for an automobile according to claim 1. 7. The control device for an automobile according to claim 1, wherein the control unit case is a case of an engine control device or a throttle control device.