JPH09242576A - Intake throttle valve device for internal combustion engine - Google Patents

Abstract

(57) Abstract: An object of the present invention is to use a type having one pressure inlet, so that the detection accuracy does not decrease, and the influence of foreign matter or the like entering the pressure inlet passage is prevented. It is an object of the present invention to provide an intake throttle valve device for an internal combustion engine, which does not suffer a decrease in detection sensitivity. SOLUTION: An intake passage 1 is provided downstream of an intake throttle valve 20.
One end of the inner wall 14 forming the valve 6 is open and the other end is connected to the pressure detecting portion of the pressure sensor 40. The pressure introducing passage 30 for introducing the pressure downstream of the throttle valve 20 into the pressure sensor 40 is connected to the pressure introducing port 38. To the connecting portion of the short-circuit passage 32a and the short-circuit passage 32a, which is disposed orthogonal to the short-circuit passage 32a and in which the flow line of the fluid flowing inside the short-circuit passage 32a rapidly changes. The dummy space 3 that is provided and has a larger cross-sectional area than the cross-sectional area of the short-circuit passage 32a.
4a and the dummy space 34b connected to the short-circuit passage 32b.
I made it consist of.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake throttle valve device for an internal combustion engine, and more particularly to an intake valve for an internal combustion engine which adopts a speed density system using an intake pipe pressure as one of input signals of an electronically controlled fuel injection device. The present invention relates to a throttle valve device.

[0002]

2. Description of the Related Art Conventionally, in a multi-cylinder internal combustion engine, the pressure on the downstream side of an intake throttle valve provided in a main intake passage is detected by a pressure sensor, and this detected pressure signal is used to determine a fuel injection amount. There is known an electronically controlled fuel injection device that determines a fuel injection amount by electronic control as an input signal. In this device, a pressure sensor for detecting the pressure is attached to the intake throttle valve device of the internal combustion engine to detect the pressure on the downstream side of the intake throttle valve.

As the intake throttle valve device for an internal combustion engine, for example, two types are known. One of them is, for example, JP-A-63-229341 and Japanese Utility Model Laid-Open No. 2-91.
As described in Japanese Patent Application No. 931, Japanese Utility Model Laid-Open No. 4-109346 and Japanese Patent Application Laid-Open No. 3-277935, it has two pressure introducing ports. The other one has a single pressure inlet as described in, for example, Japanese Utility Model Laid-Open No. 62-162360.

[0004]

When detecting the pressure of the intake pipe downstream of the intake throttle valve of the internal combustion engine as described above, water, oil, gasoline, foreign matters, etc. flowing in the intake pipe enter the pressure introducing passage, Due to the pressure change in the intake pipe or the intake pressure pulsation of the engine, the pressure may reach the inside of the pressure sensor, hinder the detection of the intake pipe pressure by the pressure sensor, or destroy the pressure sensor detection unit.

The former one having two pressure introducing ports introduces air into one of the pressure introducing passages from one of the pressure introducing passages to introduce foreign matter or the like entering the pressure introducing passage to another pressure introducing passage. I try to discharge it from the mouth.

However, by having two pressure introducing ports, the intake pressure pulsation from one pressure introducing port and the intake pressure pulsation from the other pressure introducing port interfere with each other and the intake pressure pulsation is amplified, As a result, there is a problem that the pressure detection accuracy of the pressure sensor is reduced.

Further, in the latter one having one pressure introducing port, since there is one inlet, interference of intake pressure pulsation does not occur, but foreign substances etc. that have entered the pressure introducing passage are effectively Since it cannot be excluded, for example, the actual exploitation Sho 62-162360
As described in the publication, a filter or the like is arranged in the middle of the pressure introducing passage to prevent foreign matter or the like from reaching the pressure sensor.

However, the method using a filter has a problem that the detection sensitivity is lowered because foreign matter or the like is attached to the filter and the filter is clogged.

An object of the present invention is to use a type having one pressure inlet, so that the detection accuracy is not deteriorated, and further, the detection sensitivity is not affected by foreign matter or the like that has entered the pressure introduction passage. SUMMARY OF THE INVENTION It is an object of the present invention to provide an intake throttle valve device for an internal combustion engine that does not decrease.

[0010]

To achieve the above object, the present invention provides a throttle body having an inner wall forming an intake passage, an intake throttle valve rotatably attached to the intake passage, and A pressure sensor for detecting the pressure downstream of the intake throttle valve, one end is opened in the inner wall forming the intake passage downstream of the intake throttle valve, the other end is connected to the pressure detection unit of the pressure sensor, In an intake throttle valve device for an internal combustion engine having a pressure introducing passage for introducing the pressure downstream of the throttle valve to the pressure sensor, the pressure introducing passage includes a first passage communicating with the opening, and the first passage. With respect to the second passage in which the streamline of the fluid flowing inside the first passage and the first passage and the second passage are connected to each other, and the cross section of the first passage is smaller than that of the first passage. Such as a large dummy space It is those that so as to constitute,
With such a configuration, foreign matter and the like can be removed in the dummy space.

In the intake throttle valve device for the internal combustion engine,
Preferably, the first passage and the second passage are connected at a right angle, and with this configuration,
This makes it possible to effectively separate the intake air and foreign matter.

In the intake throttle valve device for the internal combustion engine,
Preferably, the dummy space has a rectangular parallelepiped shape,
The side wall is configured to be orthogonal to the streamline of the fluid flowing through the first passage, and with this configuration,
The separated foreign matter can be effectively trapped.

In the intake throttle valve device for the internal combustion engine,
Preferably, the dummy space has a cylindrical shape.

In the intake throttle valve device for the internal combustion engine,
Preferably, the cross-sectional area of the second passage is made smaller than the cross-sectional area of the first passage, and such a configuration makes it possible to reduce the width of pressure fluctuation.

In the intake throttle valve device for the internal combustion engine,
Preferably, a second dummy space, which is connected to the second passage and has a cross-sectional area larger than the cross-sectional area of the second passage, is further provided. It is possible to improve the removal efficiency of.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake throttle valve device for an internal combustion engine according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 5. FIG. 1 is a plan view of an intake throttle valve device for an internal combustion engine according to an embodiment of the present invention as seen from the downstream side, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 1
4 is a cross-sectional view taken along line BB of FIG. 4, FIG. 4 is an explanatory diagram of a foreign matter removing effect by the intake throttle valve device of the internal combustion engine according to one embodiment of the present invention, and FIG. FIG. 4 is an explanatory diagram of a pressure fluctuation range by an intake throttle valve device of an internal combustion engine.

In FIG. 1, an intake throttle valve 20 for adjusting the flow passage area of the main intake passage is rotatably attached to the main intake passage inside the throttle body 10. The intake throttle valve 20 is composed of a circular valve body 22 and a valve shaft 24 to which the valve body 22 is fixed. The valve shaft 24 is rotatably mounted inside the throttle body 10.
By rotating the valve shaft 24 integrally with the drive lever 26,
The drive lever 26 is rotated via the accelerator cable in accordance with the amount of depression of an accelerator pedal (not shown), and the intake throttle valve 20 adjusts the flow passage area.

Next, the pressure introducing passage 30 formed on the end surface 12 side of the throttle body 10 will be described. A surge tank (not shown) is connected to the end surface 12 of the throttle body 10 and is further connected to the engine.

The pressure introducing passage 30 for introducing the intake pipe pressure on the intake downstream side of the intake throttle valve 20 is provided with a throttle body 10.
A short-circuit passage 32a formed in the end surface 12 of the throttle body 10, a rectangular parallelepiped dummy space 34a opened in the end surface 12 of the throttle body 10, and a short-circuit passage formed in the end surface 12 of the throttle body 10 in the groove shape. 32b, a cylindrical dummy space 34b formed to open at the end surface 12 of the throttle body 10, a sensor passage 36a formed obliquely inside the throttle body 10, and the throttle body 1
The sensor passage 36b is formed obliquely inside 0.

One end of the short-circuit passage 32a opens into the inner wall 14 of the throttle body 10 and constitutes a pressure introduction port 38. The position where the pressure introduction port 38 is formed is the position of the shaft end of the valve shaft 24 of the intake throttle valve 20. The pressure introducing port 38 is provided on a surface that is perpendicular to a surface that passes through the central axis of the valve shaft and that is parallel to the intake air. The direction in which the short circuit passage 32a extends is parallel to the axial direction of the valve shaft 24. The other end of the short circuit passage 32a is connected to the dummy space 34a.

A dummy space 34 is provided at one end of the short-circuit passage 32b.
a and the other end thereof is connected to the dummy space 34b. The central axis of the short-circuit passage 32b is
It is orthogonal to the central axis of a. The position where the dummy space 34a is provided is a position where the central axis of the short circuit passage 32b and the central axis of the short circuit passage 32a are orthogonal to each other.

In the rectangular parallelepiped dummy space 24a, one surface of its side wall is orthogonal to the central axis of the short circuit passage 32a.

One end of the sensor passage 36a has a dummy space 3
4b, and the other end communicates with the sensor passage 36b. The sensor passage 36a is formed obliquely with respect to the sensor passage 36b and the dummy space 34b for the following reason. That is, the dummy space 34b communicating with the sensor passage 36a forms a pair with the reference hole 50 formed in the end surface 14 of the throttle body 10 and is also used as a reference hole. The surge tank and the like are defined in the positions shown in the drawings. On the other hand, the position of the sensor passage 36b into which the pressure introduction pipe 42 of the pressure sensor 40 is inserted is also defined substantially at the illustrated position in relation to the mounting position of the pressure sensor 40 on the throttle body 10. Therefore, the sensor passage 36a is formed obliquely with respect to the sensor passage 36b and the short-circuit passage 32b due to the influence of the deviation between the dummy space 34b and the sensor passage 36b.

A pressure sensor 40 is fixed to the side surface of the throttle body 10. The pressure introducing pipe 42 of the pressure sensor 40 is inserted into the sensor passage 36b.
The pressure sensor 40 is provided with a semiconductor pressure / electricity conversion unit (not shown).

By connecting and fixing a surge tank or the like to the end surface 12 of the throttle body 10, a groove-shaped short-circuit passage 32a and a short-circuit passage 32b and an open dummy space 34 are formed.
The a and the dummy space 34b are covered. As a result, the short circuit passage 32a, the dummy space 34a, the short circuit passage 32b, the dummy space 34b, the sensor passage 36a, the sensor passage 36b.
Are communicated with each other to form a pressure introducing passage 30. The intake pressure introduced from the pressure introducing port 38 of the pressure introducing passage 30 is transmitted through the pressure introducing passage 30, passes through the pressure introducing pipe 42 of the pressure sensor 40, and is converted into an electric signal by the pressure sensor 40.

Next, the shape of the pressure inlet 38 will be described with reference to FIG. FIG. 2 is a sectional view taken along the line AA of FIG.

Inside the throttle body 10, a cylindrical main intake passage 1 having a diameter of φ50 mm at the most restricted position.
6 is formed by the inner wall 14. Throttle body 10
An intake pipe (not shown) on the air cleaner side is connected to the intake upstream side, and a surge tank (not shown) is connected on the intake downstream side.

The throttle body 10 has a main intake passage 1
A rotatable intake air throttle valve 20 for adjusting the flow passage area 6 is attached. The intake throttle valve 20 includes a valve shaft 24 and a valve element 22 fixed to the valve shaft 24.
In the state shown in FIG. 2, the intake throttle valve 20 is in the fully closed state, and from this fully closed state, the valve shaft 24 rotates in the clockwise arrow C direction in FIG.

A pressure inlet 38 is opened in the inner wall 14 at a position below the valve shaft 24, on the downstream side of the intake throttle valve 20 of the throttle body 10. The intake pressure introduced from the pressure introducing port 38 passes through the pressure introducing passage inside the throttle body 10 and is detected by the pressure sensor 40.

Next, the structure of the main part of the pressure introducing passage will be described with reference to FIG. FIG. 3 is a sectional view taken along the line BB of FIG.

As shown in the figure, the short-circuit passage 32a of the pressure introducing passage 30 has a rectangular shape in a state where the cross section is represented by a plane orthogonal to the central axis of the passage. Since the dummy space 34a is a rectangular parallelepiped, its cross-sectional shape is rectangular. The cross-sectional area of the dummy passage 32a is equal to that of the short-circuit passage 3
It is larger than the cross-sectional area of 2a. Short circuit passage 32b
Has a rectangular cross-sectional shape like the short-circuit passage 32a, and the cross-sectional area is also equal to the cross-sectional area of the short-circuit passage 32a.

The dummy space 34b has a cylindrical shape, and the cross-sectional area when the cross section is represented by a plane passing through the center of the cylinder is larger than the cross-sectional areas of the short-circuit passages 32a and 32b. The sensor passage 36a and the sensor passage 36b have the same cross-sectional shape, and the cross-sectional shape is circular. The sensor passage 36b has a size into which the pressure introducing pipe 42 of the pressure sensor 40 can be inserted.

The sensor passage 36a is formed obliquely with respect to the sensor passage 36b and the dummy space 34b for the following reason. That is, since the sensor passage 36a is formed in the end surface 14 of the throttle body 10 in a groove shape by a die-casting method, it is necessary to open the end surface in a groove shape, and the sensor passage 36a is defined at the illustrated position. On the other hand, the pressure sensor 4
Sensor passage 36b into which the zero pressure introduction pipe 42 is inserted
The position of is also defined substantially at the illustrated position in relation to the mounting position of the pressure sensor 40 on the throttle body 10. Therefore, the sensor passage 36a is formed obliquely with respect to the sensor passage 36b and the short-circuit passage 32b due to the influence of the deviation between the short-circuit passage 32b and the sensor passage 36b.

By connecting and fixing a surge tank or the like to the end surface 12 of the throttle body 10, a groove-shaped short-circuit passage 32a and a short-circuit passage 32b and an open dummy space 34 are formed.
The a and the dummy space 34b are covered. As a result, the short circuit passage 32a, the dummy space 34a, the short circuit passage 32b, the dummy space 34b, the sensor passage 36a, the sensor passage 36b.
Are communicated with each other to form a pressure introducing passage 30. The intake pressure introduced from the pressure introducing port 38 of the pressure introducing passage 30 is transmitted through the pressure introducing passage 30, passes through the pressure introducing pipe 42 of the pressure sensor 40, and is converted into an electric signal by the pressure sensor 40.

As described above with reference to FIGS. 1 to 3, the pressure introducing passage 30 according to the present embodiment is
Since the type of the pressure introducing port 38 is one, as described above, there is no influence of the interference of the intake pressure pulsation in the type having the two pressure introducing ports. However, since clean air cannot be introduced into the pressure introducing passage, foreign matters and the like enter the pressure introducing passage 30. With respect to the intrusion of the foreign matter, the present embodiment is configured as follows.

The central axis of the short-circuit passage 32a and the short-circuit passage 32b
Since the central axes of the two are orthogonal to each other, the streamline from the short-circuit passage 32a to the short-circuit passage 32b is bent, and the direction of the streamline is suddenly changed. Moisture, oil, gasoline, and other foreign matter flowing in the intake pipe have a larger mass than air, so they cannot be completely bent at the bent part of the streamline and go straight ahead. Can be separated.

Here, further, in the bent portion of the streamline,
The dummy space 34a is provided, and the cross-sectional area of the dummy space 34a is made larger than that of the short-circuit passage 32a.
When foreign matter such as air flows into the short-circuit passage 32a, the air has a small mass, so that the air enters the dummy space 34a and the cross-sectional area increases, so that the flow velocity decreases. The flow velocity does not decrease even when entering the space 34a, and the two are separated. Then, the foreign matter whose flow velocity does not decrease goes straight on, collides with the side wall of the front dummy space 34a, and is trapped by the side wall.

Here, the dummy space 34a has a rectangular parallelepiped shape, and the side wall of the flat plate is connected to the short-circuit passage 32a.
By making it orthogonal to the central axis of, that is, orthogonal to the streamline of the short-circuit passage 32a, it is possible to efficiently trap foreign matter that has gone straight ahead.

Therefore, by providing the dummy space 34a configured as described above, foreign matters can be effectively separated and the air from which the foreign matters have been removed can be introduced into the short-circuit passage 32b. .

Further, the short-circuit passage 32b is provided in the dummy space 3
4b, the foreign matter component contained in the passing air is removed also in the dummy space 34b. Therefore, the central axis of the short-circuit passage 32b and the central axis of the sensor passage 36a intersect each other, so that the short-circuit passage 32a
The streamline from the to the short-circuit passage 32b is bent, and the direction of the streamline is suddenly changed. Originally, it is effective to make this change in direction at a right angle, but it is made oblique based on other design factors. Foreign matter flowing in the intake pipe is
Since the mass thereof is larger than that of air, the streamline cannot be bent at the bent portion and goes straight, so that the air and the foreign matter can be separated.

Here, further, at the bent portion of the streamline,
The dummy space 34b is provided, and the cross-sectional area of the dummy space 34b is made larger than that of the short-circuit passage 32b.
When foreign matter or the like flows into the short-circuit passage 32b, the mass of the air is small, so that the air enters the dummy space 34b and the cross-sectional area increases, so that the flow velocity decreases. The flow velocity does not decrease even when entering the space 34b, and the two are separated. Then, the foreign matter whose flow velocity does not decrease goes straight on, collides with the side wall of the front dummy space 34b, and is trapped by the side wall.

Here, since the dummy space 34b has a cylindrical shape, it is possible to trap a foreign matter that has gone straight ahead. The dummy space 34b is
Similar to the dummy space 34a, a rectangular parallelepiped has a higher trapping efficiency, but has a cylindrical shape due to the design factor as described above. The dummy space 34b is
Since it is the second-stage trap and most foreign matters are trapped in the dummy space 34a which is the first trap, there is no practical problem even if it is formed in a cylindrical shape. The trap efficiency of each dummy space will be described later with reference to FIG.

Therefore, by providing the dummy space 34b configured as described above, foreign matter and the like can be effectively separated, and air from which foreign matter and the like has been removed can be introduced into the sensor passage 36a. it can.

As a result, most foreign matter can be removed from the air that reaches the pressure introducing pipe 42 of the pressure sensor 40, so that it is possible to prevent foreign matter from adhering to the pressure sensor and deteriorating the detection sensitivity.

Since the trapped foreign substances and the like are accumulated in the dummy spaces 34a and 34b, it is necessary to secure a certain volume so that the passage is not clogged even if the foreign substances and the like are accumulated.

Further, the dummy spaces 34a and 34b have a larger cross-sectional area than the cross-sectional areas of the short-circuit passages 32a and 32b connected to the preceding stages thereof so as to separate air and foreign matters and the like, and the separation efficiency thereof. Is due to the ratio of cross-sectional areas, and this point will be described later with reference to FIG.

Next, the effect of removing foreign matter in the intake throttle valve device for the internal combustion engine according to the embodiment of the present invention will be described with reference to FIG.

In FIG. 4, the horizontal axis indicates the position of the pressure introducing passage, and the vertical axis indicates the amount of foreign matter invading.
In the experiment, a part of the intake throttle valve device of the internal combustion engine having the structure shown in FIGS. 1 to 3 was formed of plastic and the pressure introduction passage was visualized.

As the foreign matter to be introduced, blow-by gas containing water, oil and soot in which oil is burned is used, and these foreign matters are introduced from the upstream side of the intake passage.

Further, the dimensions of each part are as follows. The cross-sectional shape of the short-circuit passage 32a is rectangular, and in the state shown in FIG. 3, the width is 2 mm, the height is 3 mm, and the cross-sectional area is 6 mm.
It was set to mm ² . The dummy space 34a has a rectangular cross-section, and has a width of 3 mm and a height of 4 mm in the state shown in FIG.
The cross-sectional area was 12 mm ² . Therefore, the dummy space 34a
The cross-sectional area of is equal to twice the cross-sectional area of the short circuit passage 32a. The cross-sectional shape of the short-circuit passage 32b is 2 mm × 3 mm, like the short-circuit passage 32a.

In the state shown in FIG. 3, the size of the dummy space 34b is 5 mm in width and 7 mm in height, and the cross-sectional area is 36 mm ² including the top of the triangular drill hole on the top. The cross-sectional area of the space 34b is 6 times the cross-sectional area of the short circuit passage 32b.

The cross-sectional area of the sensor passages 36a and 36b is about 6 mm ² , which is four times the cross-sectional area (about 1.5 mm ² ) of the pressure introducing pipe 42 (inner diameter φ2.5 mm).

The experiment was conducted under the above conditions, and the amount of foreign matter invaded was visually measured. The result is shown in FIG. In FIG. 4, the solid line X indicates the amount of foreign matter entering the position of the pressure introducing passage measured according to the present embodiment. It was not possible to confirm that water, oil, etc. entered the pressure introducing passage, but it was possible to visually confirm the amount of soot attached due to the entry of blow-by gas. At the position of the pressure sensor detection portion, almost 100% of foreign matter is removed. As its breakdown, the dummy space 34a
In, almost 85% of the foreign matter is trapped and removed. After that, some soot adheres to the wall surface in the dummy space 34b on the flow side, but the remaining 15% of the foreign matter is removed in the dummy space 34b, and soot is almost not adhered to the sensor passage 36a. It was confirmed that 100% of the foreign matter was removed.

In FIG. 4, the dotted line Y is shown as a comparative example, and here, the dummy space 3 having a large sectional area is shown.
4a and 34b are not used, and the short circuit passage 32a and the short circuit passage 3 are not used.
A bend is provided between 2b and a bend is provided between the short circuit passage 32b and the sensor passage 36a. In Comparative Example Y, about 15% of foreign matter can be prevented from entering due to the effect of the curved corner portion, but it is understood that 85% reaches the pressure sensor detection portion.

Further, an experiment was conducted by changing the cross-sectional area of the dummy space 34a. If the cross-sectional area of the dummy space 34a is set to be 1.5 times or more of the cross-sectional area of the short-circuit passage 32a, the pressure sensor detection portion is penetrated. It was found that almost all foreign matter could be removed.

Since the dummy spaces 34a and 34b act as a space for accumulating the separated foreign matter at the same time as separating the foreign matter, it is better to increase the volume of the space to allow the accumulated foreign matter to pass through. Preferred to prevent clogging.

Further, the damping effect of the intake pressure pulsation in the intake throttle valve device for the internal combustion engine according to the embodiment of the present invention will be described with reference to FIG.

The intake pressure pulsates in synchronization with the rotation of the engine. An electric signal indicating the pressure detected by the pressure sensor is taken into the electronically controlled fuel injection device via the A / D converter. The A / D converter samples the pulsating pressure signal, converts it into a digital signal, and obtains an average value of the pulsating pressure signal by a microcomputer in the electronically controlled fuel injection device. Here, if the pulsation of the intake pressure is large, that is, if the pressure fluctuation range is large, the error when converting to a digital signal becomes large, and the calculated average value is not stable and fluctuates.

On the other hand, in the intake throttle valve device of the internal combustion engine configured as shown in FIGS. 1 to 3, the pressure fluctuation width at the position of the pressure sensor was measured, and FIG.
It was as shown. That is, in FIG. 5, the horizontal axis represents the position of the pressure introducing passage, and the vertical axis represents the pressure fluctuation width.

When the pressure at each portion of the pressure introducing passage was measured in the state where the pressure varying width at the opening end, that is, the position of the pressure introducing port 38 was 200 mmHg, the pressure varying width was greatly attenuated at the position of the dummy space 34a. It was confirmed. This is because the dummy section 34a has a larger cross-sectional area than the preceding short-circuit passage 32a, so that the pulsation is absorbed by its spatial expansion.
Pressure fluctuation range at the position of the pressure inlet 38 is 200 mm
At Hg, the pressure fluctuation width at the position of the dummy space 34a was 160 mmHg. Therefore, the dummy space 34
In addition to trapping foreign substances, a has the effect of damping intake pressure pulsation.

Further, it was confirmed that the pressure fluctuation width also attenuates at the position of the dummy space 34b. The pressure fluctuation width at the position of the dummy space 34b was 85 mmHg. The dummy space 34b has the effect of trapping foreign matter, but has a great effect of damping the intake pressure pulsation.
This is because the cross-sectional area of the dummy space 34b is the short-circuit passage 32b.
The cross-sectional area of the dummy space 34a is larger than twice the cross-sectional area of the short-circuit passage 32b, so that the effect of damping the intake pressure pulsation is large.

The pressure fluctuation width at the position of the pressure sensor detecting portion is attenuated to 80 mmHg.

As described above, according to the present embodiment, by using the type having one pressure inlet, the detection accuracy does not decrease, and by using the dummy space, the pressure can be reduced. The detection sensitivity is not deteriorated without being affected by foreign matter or the like that has entered the introduction passage.

By using the dummy space,
The intake pressure pulsation can be attenuated and a stable sensor output can be obtained.

Further, by using two dummy spaces, the effect of removing foreign matters and the like is improved, and the effect of damping intake pressure pulsation is also improved.

In addition, in the method of using a filter for removing foreign matters and the like, when water adheres to the filter, the filter freezes when the outside air temperature decreases and the pressure is not transmitted to the pressure sensor. It is possible that the intake negative pressure of the engine cannot be detected and the engine cannot be started, but in order to remove foreign substances without using a filter,
There is no problem with the startability of the engine.

Further, since the first dummy space has a rectangular parallelepiped shape and its side wall is orthogonal to the streamline of the short-circuit passage,
The foreign matter or the like separated from the air in the dummy space goes straight and collides with the side wall, so that the foreign matter or the like can be effectively trapped.

Next, an intake throttle valve device for an internal combustion engine according to another embodiment of the present invention will be described with reference to FIGS. 6 to 8. 6 is a plan view of an intake throttle valve device for an internal combustion engine according to another embodiment of the present invention as viewed from the downstream side, FIG. 7 is a sectional view taken along line CC of FIG. 6, and FIG. FIG. 9 is an explanatory diagram of a pressure fluctuation range by an intake throttle valve device for an internal combustion engine according to another embodiment of the present invention.

6, the same reference numerals as those in FIG. 1 indicate the same parts. Since the basic configurations of the throttle body 10, the intake throttle valve 20, and the pressure sensor 40 are the same as those in FIG. 1, the description thereof will be omitted.

The structure of the pressure introducing passage 30 'will be described below. The pressure introducing passage 30 ′ for introducing the intake pipe pressure on the intake downstream side of the intake throttle valve 20 is provided in the throttle body 1
0 is formed on the end surface 12 of the throttle body 10 in the shape of a groove, a cylindrical dummy space 34a 'opened to the end surface 12 of the throttle body 10, and the end surface 12 of the throttle body 10 is formed in the shape of a groove. A short-circuit passage 32b ', a cylindrical dummy space 34b formed by opening at the end surface 12 of the throttle body 10, a sensor passage 36a' formed obliquely inside the throttle body 10, and an inside of the throttle body 10. Sensor passage 36b formed obliquely to the
It is composed of

One end of the short-circuit passage 32a opens into the inner wall 14 of the throttle body 10 and constitutes a pressure inlet 38. The position where the pressure introduction port 38 is formed is the position of the shaft end of the valve shaft 24 of the intake throttle valve 20. The pressure introducing port 38 is provided on a surface that is perpendicular to a surface that passes through the central axis of the valve shaft and that is parallel to the intake air. The direction in which the short circuit passage 32a extends is parallel to the axial direction of the valve shaft 24. The other end of the short circuit passage 32a is connected to the dummy space 34a '.

One end of the short circuit passage 32b 'has a dummy space 3
4a 'and the other end is connected to the dummy space 34b. The central axis of the short-circuit passage 32b 'is orthogonal to the central axis of the short-circuit passage 32a. Dummy space 3
The position where 4a 'is provided is a position where the central axis of the short-circuit passage 32b' and the central axis of the short-circuit passage 32a are orthogonal to each other.

The cylindrical dummy space 34a 'faces its side wall so as to be orthogonal to the central axis of the short-circuit passage 32a.

The dummy space 34a in FIG. 1 is a rectangular parallelepiped and is integrally formed with the throttle body by a die casting method, whereas the cylindrical dummy space 34a 'is formed by cutting with a drill. I have to. This is suitable when the dummy space 34a cannot be formed by the die-cast manufacturing method in the case of a small displacement engine or the like having a small throttle bore diameter.

One end of the sensor passage 36a 'communicates with the dummy space 34b, and the other end communicates with the sensor passage 36b. The sensor passage 36a ′ is the sensor passage 36a.
It is formed obliquely with respect to b and the dummy space 34b.

A pressure sensor 40 is fixed to the side surface of the throttle body 10. The pressure introducing pipe 42 of the pressure sensor 40 is inserted into the sensor passage 36b.
The pressure sensor 40 is provided with a semiconductor pressure / electricity conversion unit (not shown).

By connecting and fixing a surge tank or the like to the end surface 12 of the throttle body 10, the groove-shaped short-circuit passage 32a and the short-circuit passage 32b ', and the opened dummy space 3 are formed.
4a 'and the dummy space 34b are covered. As a result, the short-circuit passage 32a, the dummy space 34a ', the short-circuit passage 3
2b ', the dummy space 34b, the sensor passage 36a', and the sensor passage 36b communicate with each other to form the pressure introducing passage 30. The intake pressure introduced from the pressure introducing port 38 of the pressure introducing passage 30 is transmitted through the pressure introducing passage 30, passes through the pressure introducing pipe 42 of the pressure sensor 40, and is converted into an electric signal by the pressure sensor 40.

The position where the pressure introducing port 38 is formed is the same as that shown in FIG.
0 is the position of the inner wall 14 which is on the downstream side of the intake throttle valve 20 and below the valve shaft 24.

Next, the structure of the main part of the pressure introducing passage will be described with reference to FIG. FIG. 7 is a sectional view taken along the line CC of FIG.

As shown in the figure, the short-circuit passage 32a of the pressure introducing passage 30 has a rectangular shape in a state where a cross section is represented by a plane orthogonal to the central axis of the passage. Since the dummy space 34a 'has a cylindrical shape, the sectional shape passing through the central axis thereof is rectangular. The cross-sectional area of the dummy space 34a is larger than the cross-sectional area of the short circuit passage 32a.
The short circuit passage 32b 'has a rectangular cross-sectional shape,
The cross-sectional area is smaller than the cross-sectional area of the short-circuit passage 32a, and is equal to the cross-sectional area of the inner diameter portion of the pressure introduction pipe 42 of the pressure sensor 40.

The dummy space 34b has a cylindrical shape, and the cross-sectional area when the cross section is represented by a plane passing through the center of the cylinder is larger than the cross-sectional areas of the short-circuit passages 32a and 32b '.
The cross-sectional shape of the sensor passage 36a 'is circular, and its cross-sectional area is equal to the cross-sectional area of the inner diameter of the pressure introducing pipe 42 of the pressure sensor 40. The cross-sectional shape of the sensor passage 36b is circular, and the size is such that the pressure introduction pipe 42 of the pressure sensor 40 can be inserted.

The sensor passage 36a 'is the sensor passage 36b.
It is formed obliquely with respect to the dummy space 34b.

By connecting and fixing a surge tank or the like to the end surface 12 of the throttle body 10, the groove-shaped short-circuit passage 32a and the short-circuit passage 32b ', and the opened dummy space 3 are formed.
4a 'and the dummy space 34b are covered. As a result, the short-circuit passage 32a, the dummy space 34a ', the short-circuit passage 3
2b ', the dummy space 34b, the sensor passage 36a', and the sensor passage 36b communicate with each other to form the pressure introducing passage 30. The intake pressure introduced from the pressure introducing port 38 of the pressure introducing passage 30 is transmitted through the pressure introducing passage 30, passes through the pressure introducing pipe 42 of the pressure sensor 40, and is converted into an electric signal by the pressure sensor 40.

As described above, as described with reference to FIGS. 6 and 7, the pressure introducing passage 30 according to the present embodiment is
Since the type of the pressure introducing port 38 is one, as described above, there is no influence of the interference of the intake pressure pulsation in the type having the two pressure introducing ports. However, since clean air cannot be introduced into the pressure introducing passage, foreign matters and the like enter the pressure introducing passage 30. With respect to the intrusion of the foreign matter, the present embodiment is configured as follows.

The central axis of the short-circuit passage 32a and the short-circuit passage 32
Since the central axes of b ′ are orthogonal to each other, the streamline from the short-circuit passage 32a to the short-circuit passage 32b ′ is bent, and the direction of the stream is suddenly changed. Moisture flowing in the intake pipe,
Since oil, gasoline, and other foreign matter have a larger mass than air, they cannot be bent at the part where the streamline is bent, and they go straight ahead, so that the air and foreign matter can be separated. it can.

Here, further, in the bent portion of the streamline,
The dummy space 34a 'is provided, and the cross-sectional area of the dummy space 34a' is made larger than that of the short-circuit passage 32a. When foreign matter or the like flows into the short circuit passage 32a,
Since air has a small mass, it enters the dummy space 34a ', and its flow velocity decreases due to the increase in cross-sectional area. However, for foreign matter having a large mass, the flow velocity does not decrease even if it enters the dummy space 34a'. , The two are separated. Then, the foreign matter whose flow velocity does not decrease goes straight ahead, collides with the side wall of the front dummy space 34a ', and is trapped by the side wall.

Here, the dummy space 34a 'has a cylindrical shape, and further, the side wall thereof is orthogonal to the central axis of the short-circuit passage 32a, that is, orthogonal to the streamline of the short-circuit passage 32a, so that the dummy space 34a' goes straight. It is possible to trap foreign matters efficiently.

Therefore, by providing the dummy space 34a 'configured as described above, foreign matter and the like can be effectively separated, and the air from which the foreign matter and the like have been removed is introduced into the short-circuit passage 32b'. You can

Further, the short-circuit passage 32b 'communicates with the dummy space 34b, and foreign matter components contained in the passing air are removed also in the dummy space 34b. Therefore, the central axis of the short-circuit passage 32b 'and the central axis of the sensor passage 36a' intersect each other, so that the short-circuit passage 3
The streamline extending from 2a to the short-circuit passage 32b 'is bent and abruptly changes in direction. Originally, it is effective to make this change in direction at a right angle, but it is made oblique based on other design factors. Since the foreign matter or the like flowing in the intake pipe has a larger mass than the air, it cannot be completely bent at the bent portion of the streamline, and it goes straight ahead, so that the air and the foreign matter can be separated.

Here, further, in the bent portion of the streamline,
The dummy space 34b is provided, and the cross-sectional area of the dummy space 34b is made larger than that of the short-circuit passage 32b '. When foreign matter such as air flows into the short-circuit passage 32b ', the air has a small mass, so the air enters the dummy space 34b and the cross-sectional area increases, so that the flow velocity decreases. The flow velocity does not decrease even when entering the dummy space 34b, and the two are separated. Then, the foreign matter whose flow velocity does not decrease goes straight on, collides with the side wall of the front dummy space 34b, and is trapped by the side wall.

Here, since the dummy space 34b has a cylindrical shape, it is possible to trap foreign matter and the like that have gone straight ahead. The dummy space 34
b is a trap in the second stage, and most foreign matters are in the first
Since it is trapped in the dummy space 34a 'which is a trap of the above, there is no problem in practical use even if it has a cylindrical shape.

Therefore, by providing the dummy space 34b configured as described above, foreign matter and the like are effectively separated, and the air from which foreign matter and the like has been removed is further introduced into the sensor passage 36a '. You can

As a result, most foreign matters can be removed from the air reaching the pressure introducing pipe 42 of the pressure sensor 40, so that it is possible to prevent the foreign matter from adhering to the pressure sensor and lowering the detection sensitivity.

In the dummy spaces 34a 'and 34b,
Since trapped foreign matters and the like are accumulated, it is necessary to secure a certain volume so that the passage is not clogged even if the foreign matters and the like are accumulated.

Further, the dummy spaces 34a 'and 34b have a larger cross-sectional area than the cross-sectional areas of the short-circuit passages 32a and 32b' connected to the preceding stages, so that air and foreign matters are separated from each other.

Next, the effect of removing foreign matter in the intake throttle valve device for an internal combustion engine according to another embodiment of the present invention will be described.

Here, the dimensions of each part are as follows. The short-circuit passage 32a has a rectangular cross-sectional shape, and in the state shown in FIG. 7, the width is 2 mm, the height is 3 mm, and the cross-sectional area is 6 mm.
It was set to mm ² . The dummy space 34a 'has a rectangular cross-sectional shape, and in the state shown in FIG. 7, a width of 6 mm and a height of 4 mm.
The cross-sectional area was 24 mm ² . Therefore, the dummy space 3
The cross-sectional area of 4a 'is 4 times the cross-sectional area of the short circuit passage 32a. The cross section of the short circuit passage 32b 'is 1.5 mm x 2 m
m, which is ½ of the cross-sectional area of the short circuit passage 32a.

In the state shown in FIG. 7, the size of the dummy space 34b is 5 mm in width and 7 mm in height, and the cross-sectional area is 36 mm ² including the top of the triangular drill hole on the top. The cross-sectional area of the space 34b has a short-circuit passage 32b '.
12 times the cross-sectional area of

The cross-sectional area of the sensor passage 36a 'is equal to the cross-sectional area (about 1.5 mm ² ) of the pressure introducing pipe 42 (inner diameter φ2.5 mm), and the cross-sectional area of the sensor passage 36b is about 6 mm ² . The cross-sectional area (about 1.5 mm ² ) of the pressure introducing pipe 42 (inner diameter φ2.5 mm) is four times.

The experiment was conducted under the above-mentioned conditions, and the result of visually measuring the amount of foreign matter invaded was similar to that shown in FIG. That is, almost 100% of the foreign matter is removed at the position of the pressure sensor detection portion. Specifically, about 85% of foreign matter is trapped and removed in the dummy space 34a '. After that, some soot is found on the wall surface of the dummy space 34b on the flow side, but the remaining 15% of foreign matter is also removed in the dummy space 34b.
It was confirmed that almost no soot adhered to the sensor passage 36a 'and almost 100% of the foreign matter was removed. No decrease in trap was observed due to the difference in cross-sectional area.

Since the dummy spaces 34a 'and 34b act as a space for accumulating the separated foreign matter at the same time as separating the foreign matter, it is better to increase the volume of this space depending on the accumulated foreign matter. It is preferable to prevent the passage from being blocked.

Further, the damping effect of the intake pressure pulsation in the intake throttle valve device for the internal combustion engine according to another embodiment of the present invention will be described with reference to FIG.

In the intake throttle valve device for an internal combustion engine configured as shown in FIGS. 6 and 7, the pressure fluctuation width at the position of the pressure sensor was measured, and the result was as shown in FIG. That is, in FIG. 8, the horizontal axis represents the position of the pressure introducing passage, and the vertical axis represents the pressure fluctuation width.

When the pressure variation at the opening end, that is, the pressure introduction port 38 was 200 mmHg, the pressure at each part of the pressure introduction passage was measured. As a result, the pressure variation was greatly attenuated at the dummy space 34a '. It was confirmed to do. This is because the dummy section 34a 'has a larger cross-sectional area than the preceding short-circuit passage 32a, and the pulsation is absorbed by its spatial expansion. The pressure fluctuation width at the position of the pressure inlet 38 is 20
At 0 mmHg, the pressure fluctuation width at the position of the dummy space 34a 'was 110 mmHg. Therefore, the dummy space 34a 'has an effect of damping intake pressure pulsation as well as a trapping effect of foreign matters.

Furthermore, by making the cross-sectional area of the short-circuit passage 32b 'half the cross-sectional area of the short-circuit passage 32a, the effect of damping the intake pressure pulsation by the short-circuit passage 32b' also appears.

Further, it was confirmed that the pressure fluctuation width similarly attenuates at the position of the dummy space 34b. The pressure fluctuation width at the position of the dummy space 34b was 70 mmHg. The dummy space 34b has the effect of trapping foreign matter, but has a great effect of damping the intake pressure pulsation.
This is because the cross-sectional area of the dummy space 34b is the short-circuit passage 32.
It is 12 times as large as the cross-sectional area of b'and the dummy space 34a '
Of the cross-sectional area of the short-circuit passage 32b 'to the cross-sectional area of 2
Since it is larger than double, the effect of damping the intake pressure pulsation is large.

Since there is also a damping effect in the sensor passage 36a ', the pressure fluctuation width at the position of the pressure sensor detecting portion is damped to 40 mmHg.

As described above, according to the present embodiment, by using the type having one pressure inlet, the detection accuracy does not decrease, and by using the dummy space, the pressure can be reduced. The detection sensitivity is not deteriorated without being affected by foreign matter or the like that has entered the introduction passage.

By using the dummy space,
The intake pressure pulsation can be attenuated and a stable sensor output can be obtained.

Further, the effect of damping intake pressure pulsation is improved by reducing the cross-sectional area of the short-circuit passage.

Also, by using two dummy spaces, the effect of removing foreign matters and the like is improved, and the effect of damping intake pressure pulsation is also improved.

In addition, in the method of using a filter to remove foreign matters and the like, when water adheres to the filter, the filter freezes when the outside air temperature decreases and the pressure is not transmitted to the pressure sensor. It is possible that the intake negative pressure of the engine cannot be detected and the engine cannot be started, but in order to remove foreign substances without using a filter,
There is no problem with the startability of the engine.

[0113]

According to the present invention, the detection accuracy does not decrease, and the detection sensitivity does not decrease without being affected by foreign matter or the like that has entered the pressure introducing passage.

[Brief description of drawings]

FIG. 1 is a plan view of an intake throttle valve device for an internal combustion engine according to an embodiment of the present invention as viewed from the downstream side.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is an explanatory diagram of a foreign matter removing effect by the intake throttle valve device for the internal combustion engine according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram of a pressure fluctuation range by the intake throttle valve device for the internal combustion engine according to the embodiment of the present invention.

FIG. 6 is a plan view of an intake throttle valve device for an internal combustion engine according to another embodiment of the present invention, as viewed from the downstream side.

FIG. 7 is a sectional view taken along the line CC of FIG. 6;

FIG. 8 is an explanatory diagram of a pressure fluctuation range by an intake throttle valve device for an internal combustion engine according to another embodiment of the present invention.

[Explanation of symbols]

 10 ... Throttle body 12 ... Throttle body end surface 14 ... Inner wall 16 ... Main intake passage 20 ... Intake throttle valve 22 ... Valve body 24 ... Valve shaft 26 ... Drive lever 30 ... Pressure introduction passage 32a, 32b, 32a '... Short-circuit passage 34a, 34a ', 34b ... Dummy space 36a, 36a', 36b ... Sensor passage 38 ... Pressure introducing port 40 ... Pressure sensor 42 ... Pressure introducing pipe

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shigeo Tamaki 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi Car Engineering Co., Ltd.

Claims (6)

[Claims] 1. A throttle body having an inner wall forming an intake passage, an intake throttle valve rotatably attached to the intake passage, a pressure sensor for detecting a pressure downstream of the intake throttle valve, and the intake air. Downstream of the throttle valve, one end is opened to the inner wall forming the intake passage, the other end is connected to the pressure detection portion of the pressure sensor, the pressure introduction to introduce the pressure downstream of the throttle valve to the pressure sensor In an intake throttle valve device for an internal combustion engine having a passage, the pressure introduction passage has a first passage communicating with the opening, and a streamline of a fluid flowing through the first passage sharply changes with respect to the first passage. An internal combustion engine, comprising: a second passage; and a dummy space that is provided in a connecting portion between the first passage and the second passage and has a cross-sectional area larger than a cross-sectional area of the first passage. Engine intake throttle Apparatus. 2. The intake throttle valve apparatus for an internal combustion engine according to claim 1, wherein the first passage and the second passage are connected at a right angle. 3. The intake throttle valve device for an internal combustion engine according to claim 2, wherein the dummy space has a rectangular parallelepiped shape, and a side wall of the dummy space is
An intake throttle valve device for an internal combustion engine, which is orthogonal to a streamline of a fluid flowing through the first passage. 4. The intake throttle valve apparatus for an internal combustion engine according to claim 2, wherein the dummy space has a cylindrical shape. 5. An intake throttle valve for an internal combustion engine according to claim 1, wherein a cross-sectional area of the second passage is smaller than a cross-sectional area of the first passage. Valve device. 6. The intake throttle valve device for an internal combustion engine according to claim 1, further comprising a second dummy space connected to the second passage and having a cross-sectional area larger than a cross-sectional area of the second passage. An intake throttle valve device for an internal combustion engine, comprising: