JP2002206434A - Intake air controller of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent operation failure of a throttle valve generated by icing and to reduce power consumption. SOLUTION: Current flows a heater member 32, having heater wire connected thereto, printed thereon, or wound thereon along a metal core 31, when the throttle valve 22 is set near the full close position under such operating conditions that icing occurs on the inner wall surface 12 of the intake passage 11 of a resin throttle body 10. Then, icing between the end face of the throttle valve 22 and the surface of the metal core 31 or the heater member 32, including projected part 13, is eliminated instantaneously. The icing of the inner wall surface 12 of the other intake passage 11 has no effect on the opening and closing routes of the throttle valve 22. Since a necessary temperature rising portion by the heater member 32 is limited to the part of the metal core 31 exposed from the projected part 13, power consumption can be suppressed, fuel consumption can be improved, and the opening and closing operation of the throttle valve 22 can be assured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an icing of a throttle valve for controlling an amount of intake air taken into an internal combustion engine.
The present invention relates to an intake control device for an internal combustion engine that prevents malfunctions caused by the internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, as a prior art document related to an intake control device for an internal combustion engine, one disclosed in Japanese Utility Model Laid-Open No. 4-119337 is known. In this one,
Resin throttle body (throttle chamber body)
A metal cylinder is integrally provided on the inner wall surrounding the throttle valve (throttle valve), and a heating wire is wound around a groove on the outer periphery of the cylinder and heated to prevent icing of a gap between the throttle valve and the cylinder. The technology is shown.

[0003]

By the way, in the above-mentioned apparatus, a metal cylinder having a predetermined width is provided in a portion corresponding to a predetermined rotation region near the fully closed position of the throttle valve, and a groove is formed on the outer periphery thereof. Is formed by winding a heating wire, and by heating and heating this heating wire, malfunctions due to icing are prevented.However, since the heat dissipation area of the cylindrical body is large, power is consumed even if electricity is supplied for a predetermined time. There were many problems that resulted in worse fuel efficiency.

Therefore, the present invention has been made to solve such a problem, and an intake control device for an internal combustion engine capable of reliably preventing a malfunction due to icing of a throttle valve and reducing power consumption required at this time. The challenge is to provide

[0005]

According to the intake control device for an internal combustion engine of the first aspect, the vicinity of the fully closed position of the throttle valve is controlled according to the operating condition such that icing occurs on the inner wall surface of the intake passage of the throttle body. Then, an electric current is applied to the heater member on which the heater wire is joined, printed or wound along the metal core. Thereby, icing between the throttle valve end surface and the surface of the metal core or the heater member including the protruding portion is instantaneously eliminated. At this time, even if icing remains on the inner wall surface of the other intake passage, there is no effect on the opening / closing trajectory of the throttle valve. As described above, since the required temperature rising portion by the heater member is limited to the exposed portion from the protruding portion of the metal core, power consumption is suppressed, fuel efficiency is improved, and the opening and closing operation of the throttle valve is guaranteed.

According to the second aspect of the present invention, the protruding portion of the internal combustion engine has a substantially trapezoidal cross section along the direction of air flow, so that the protruding portion formed in the intake passage increases the air resistance. As a result, fuel economy is prevented from deteriorating.

According to the third aspect of the intake control apparatus for an internal combustion engine, in accordance with an operating condition in which icing occurs on the inner wall surface of the intake passage of the throttle body, the throttle valve extends along the metal core near the fully closed position of the throttle valve. An electric current is applied to the heater member to which the heater wire has been joined, printed or wound. Thereby, icing between the throttle valve end surface and the inner wall surface including the side wall surface of the metal core is instantaneously eliminated. At this time, even if icing remains on the inner wall surface of the other intake passage, there is no effect on the opening / closing trajectory of the throttle valve. As described above, since the required temperature rising portion by the heater member is limited to the exposed portion of the metal core from the intake passage, power consumption is suppressed, fuel efficiency is improved, and the opening and closing operation of the throttle valve is guaranteed.

According to the fourth aspect of the present invention, the metal core in the intake control device for an internal combustion engine has a substantially trapezoidal cross section along the direction of air flow, thereby suppressing an increase in air resistance due to the metal core from the intake passage. Fuel economy deterioration is prevented.

According to a fifth aspect of the present invention, there is provided an intake control device for an internal combustion engine.
The heater member is disposed on the inner wall surface, outer wall surface, or side wall surface of the metal core, and when the heater member is disposed on the metal core, there is a degree of freedom that various manufacturing methods can be adopted.

In the throttle valve of the intake control device for an internal combustion engine according to the present invention, the non-linear region is set by the auxiliary member so that the intake air amount near the fully closed position is gradually increased, so that the throttle valve is fully closed. A desired amount of air in the vicinity of the position can be accurately obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

Embodiment 1 FIG. 1 is a sectional view showing a main configuration of an intake control device for an internal combustion engine according to a first embodiment of the present invention.

In FIG. 1, an intake passage 11 through which air taken into an internal combustion engine (not shown) passes is formed in a throttle body 10 formed of resin. In the middle of the intake passage 11, a throttle valve 2 for adjusting the intake air amount is provided.
2 is supported by a throttle shaft 21 so as to be freely opened and closed. A part of the inner wall surface 12 of the intake passage 11 is formed with a protruding portion 13 that is concentric toward the center axis of the cross section near the fully closed position in the opening / closing trajectory of the throttle valve 22. The protrusion 13 has a substantially trapezoidal cross section along the direction of air flow, and is formed so that the inner diameter of the inner wall surface 12 of the intake passage 11 changes gradually.

The throttle valve 22 of this embodiment is
Is formed by, for example, screwing and fixing a resin auxiliary member 22b to a metal disk member 22a.

The protrusion 13 of the intake passage 11 has
An annular metal core 31 is embedded, and a heater member 32 is resistance-printed on the inner wall surface side of the metal core 31 using, for example, a heater wire or a silk-screen printing technique joined by using a resistor such as a flexible substrate. It is formed of a heater wire. The metal core 31 is exposed at the distal end face of the protruding portion 13 via the heater member 32. Therefore, the heater member 32 is opposed to and close to the periphery of the opening / closing locus of the throttle valve 22 near the fully closed position. Here, the periphery of the metal core 31 on which the heater member 32 is formed is covered with the resin of the protruding portion 13.

Next, the operation and action will be described.

If the temperature of air introduced through an air cleaner (not shown) through the intake passage 11 of the throttle body 10 is, for example, below the freezing point and the air contains moisture, as shown in FIG. This moisture is supplied to the intake passage 11
A phenomenon of freezing and sticking to the inner wall surface 12 of the rim occurs. In particular, when the throttle valve 22 is in the vicinity of the fully closed position in the opening / closing trajectory, the gap between the projection 13 formed on the inner wall surface 12 of the intake passage 11 and the throttle valve 22 is small, And the temperature of the air is further reduced by the adiabatic expansion effect, so that the ice is easily frozen.

Therefore, when a predetermined icing condition is satisfied, by energizing the heater member 32, the icing portion in the vicinity of the fully closed position in the opening / closing locus of the throttle valve 22 is instantaneously melted and turned into water. It will be. At this time, the power consumption required for energization is extremely small because it is only necessary to eliminate the icing state of the portion corresponding to the end face of the throttle valve 22. That is,
The inner wall surface 12 of the intake passage 11 before and after the throttle valve 22 in the vicinity of the fully closed position is one step lower than the protruding portion 13, and is not on the opening / closing locus of the throttle valve 22. For this reason, the throttle valve 22 opens and closes the intake passage 1 during opening and closing operations.
Even if the inner wall surface 12 is in a frozen state, it is not affected.

The heater member 32 including the metal core 31
The amount of heat that escapes to the portion other than the throttle valve 22 side due to the heat insulating properties of the resin can be reduced. Further, the protruding portion 13 of the intake passage 11 is formed in a substantially trapezoidal shape, so that the air resistance of the intake passage 11 is reduced as much as possible so that a pressure loss does not occur in the intake stroke of the internal combustion engine.

The throttle valve 22 in this embodiment is composed of a disk member 22a and an auxiliary member 22b, and the auxiliary member 22b is formed such that the leading end locus gradually becomes inside. 1 having such a configuration
By using one throttle valve 22, a nonlinear region for gradually increasing the intake air amount near the fully closed position can be set, and the intake air in the low opening region when performing ISC (Idle Speed Control). The quantity controllability can be improved.

As described above, the intake control system for an internal combustion engine according to the present embodiment is configured such that the throttle valve 22 for adjusting the intake air amount, which is the amount of air taken into the internal combustion engine (not shown), is openably and closably supported. A resin throttle body 10 having a concentric protruding portion 13 formed on a part of the inner wall surface 12 toward the center axis of the cross section, and a throttle valve 22 near the fully closed position in the opening / closing trajectory of the throttle valve 22. The surface is at least protruded 13
An annular metal core 31 buried in the intake passage 11 so as to be exposed from the air, and a heater member 32 formed by joining, printing or winding a heater wire along the metal core 31. The projection 13 of the intake control device for an internal combustion engine according to the present embodiment has a substantially trapezoidal cross section along the direction of air flow. The heater member 32 of the intake control device for an internal combustion engine according to the present embodiment is disposed on the inner wall surface of the metal core 31.

That is, the heater wire is joined along the metal core 31 in the vicinity of the fully closed position of the throttle valve 22 in accordance with the operating condition such that the inner wall surface 12 of the intake passage 11 of the resin throttle body 10 is frozen. Alternatively, an electric current is applied to the printed or wound heater member 32. Thereby, icing between the end face of the throttle valve 22 and the surface of the metal core 31 or the heater member 32 including the protrusion 13 can be instantaneously eliminated. At this time, even if icing remains on the inner wall surface 12 of the other intake passage 11, there is no effect on the opening / closing trajectory of the throttle valve 22. As described above, the required temperature rising portion by the heater member 32 is limited to the exposed portion from the protruding portion 13 of the metal core 31, so that the power consumption can be suppressed and the fuel efficiency can be improved, and the opening and closing operation of the throttle valve 22 can be performed. Can be guaranteed.

Further, the throttle valve 22 of the intake control system for an internal combustion engine according to the present embodiment has an auxiliary member 22b for setting a non-linear region where the intake air amount gradually increases near the fully closed position. That is, since the throttle valve 22 has the auxiliary member 22b fixed to the disk member 22a constituting the valve body, the intake air amount controllability in the low opening region when performing the ISC with one throttle valve 22 is optimal. Be transformed into

Next, a modification of FIG. 1 will be described with reference to the sectional view shown in FIG. In the drawings, the same reference numerals and symbols are given to components having the same configuration or corresponding portions as those in the above-described embodiment, and detailed description thereof will be omitted.

In FIG. 2, a throttle valve 22 is rotatably supported by a throttle shaft 21 in the middle of the intake passage 11 of the resin molded throttle body 10. A part of the inner wall surface 12 of the intake passage 11 is formed with a protruding portion 13 that is concentric toward the center axis of the cross section near the fully closed position in the opening / closing trajectory of the throttle valve 22. The protrusion 13 has a substantially trapezoidal cross section along the direction of air flow, and is formed so that the inner diameter of the inner wall surface 12 of the intake passage 11 changes gradually.

An annular metal core 41 is embedded in the intake passage 11, and its inner wall surface 41 a is exposed from the projection 13. On the outer wall surface 41b side of the metal core 41 opposite to the inner wall surface 41a, for example, a heater member 42 is formed by winding a heater wire. And the metal core 4
The first inner wall surface 41a is close to the periphery of the opening / closing locus of the throttle valve 22 in the vicinity of the fully closed position.

In this modification, the throttle valve 2
2 comprises only the disk member shown in FIG. Also,
It is relatively easy to form the heater member 42 on the outer wall surface 41 b side of the metal core 41, and when the heater member 42 is energized, the inner wall surface 4
1a will be heated. For this reason, ISC (Idle
Although the control of the intake air amount in the low opening range when performing Speed Control (idle rotation speed control) is somewhat inferior, the effect of preventing malfunction due to icing of the throttle valve 22 is the same as in the first embodiment described above. The description is omitted because it is the same.

As described above, the heater member 42 of the intake control device for an internal combustion engine according to the present modification includes the outer wall surface 41 of the metal core 41.
b. Here, the heater member 4 formed by winding a heater wire along the outer wall surface 41b of the metal core 41
2 has an advantage that it is easy to manufacture. And the metal core 4
1 is buried in the intake passage 11, the intake passage 11
Since only the inner wall surface 41a of the metal core 41 is exposed to the protruding portion 13, the amount of heat from the heater member 42 including the metal core 41 is reduced by the heat insulating property of the resin, so that the heat can escape to other than the throttle valve 22 side. it can.

<Embodiment 2> FIG. 3 is a sectional view showing a main part of an intake control device for an internal combustion engine according to a second embodiment of the present invention. In the drawing, the same reference numerals and symbols are given to components having the same configurations or corresponding portions as those in the first embodiment described above, and detailed description thereof will be omitted.

In FIG. 3, a throttle valve 22 is rotatably supported by a throttle shaft 21 in the middle of the intake passage 11 of the resin molded throttle body 10. In the vicinity of the fully closed position in the opening / closing locus of the throttle valve 22, an annular metal core 51 is formed toward the center axis of the cross section.
Are concentrically projected, exposed and buried in the intake passage 11. The section of the metal core 51 protruding from the inner wall surface 12 of the intake passage 11 has a substantially trapezoidal cross section along the flow direction of air, and is formed so that the inner diameter gradually changes.

On the outer wall surface 51b side of the metal core 51,
The heater member 52 is formed by winding a heater wire, for example. The inner wall surface 51a of the metal core 51 is opposed to and close to the periphery of the opening / closing trajectory of the throttle valve 22 near the fully closed position.

In this embodiment, the throttle valve 2
2 comprises only a disk member similar to FIG. The metal core 51 buried in the intake passage 11 forms a trapezoidal shape instead of the protruding portion in the first embodiment. It is relatively easy to form the heater member 52 on the outer wall surface 51b side of the metal core 51. When the heater member 52 is energized, the inner wall surface 51a is heated by the thermal conductivity of the metal core 51. Becomes

In this case, power consumption is slightly disadvantageous because the exposed surface of the metal core 51 from the resin increases. However, when manufacturing the throttle body 10 by insert molding with the resin using the metal core 51, There is an advantage that it is possible to eliminate the generation of burrs on the inner wall surface 51a of the metal core 51 at the time of the mold configuration and the molding. The effect of preventing malfunction of the throttle valve 22 due to icing is the same as that of the first embodiment, and a description thereof will be omitted.

As described above, the intake control apparatus for an internal combustion engine according to the present embodiment is configured such that the throttle valve 22 for adjusting the intake air amount, which is the amount of air taken into the internal combustion engine (not shown), is openably and closably supported. The throttle body 10 formed of resin is opposed to and proximate to the periphery of the throttle valve 22 in the vicinity of the fully closed position of the opening and closing trajectory of the throttle valve 22, and the center axis of the cross section thereof is shifted from the inner wall surface 12 of the intake passage 11. Intake passage 1 so as to project concentrically toward
1 has an annular metal core 51 embedded therein and a heater member 52 having a heater wire wound along the metal core 51. The metal core 51 of the intake control device for an internal combustion engine according to the present embodiment has a substantially trapezoidal cross section along the direction of air flow. The heater member 52 of the intake control device for an internal combustion engine according to the present embodiment is disposed on the outer wall surface 51 b of the metal core 51.

That is, depending on the operating conditions under which icing occurs on the inner wall surface 12 of the intake passage 11 of the resin throttle body 10, a heater wire is joined or formed along the metal core near the fully closed position of the throttle valve 22. An electric current is applied to the printed or wound heater member 52. Thereby, icing between the end surface of the throttle valve 22 and the inner wall surface 51a including the side wall surface of the metal core 51 can be instantaneously eliminated. At this time, even if icing remains on the inner wall surface 12 of the other intake passage 11, there is no effect on the opening / closing trajectory of the throttle valve 22. As described above, since the required temperature rising portion by the heater member 52 is limited to the exposed portion of the metal core 51 from the intake passage 11, fuel consumption can be improved by suppressing power consumption, and the opening / closing operation of the throttle valve 22 can be performed. Can be guaranteed. Furthermore,
By suppressing the air resistance passing through the intake passage 11, deterioration of fuel efficiency can be prevented.

By the way, when the throttle valve 22 is constituted only by a metal disk member as in the above-described embodiment and the modified example, the control of the intake air amount in the low opening region when performing the ISC is slightly performed. Although it was inferior, in a system that performs ISC with one throttle valve, as in FIG.
Auxiliary member 22 made of resin for disk member 22a made of metal
Needless to say, the throttle valve 22 provided with b may be used.

In the above-described embodiments, the slope portion of the substantially trapezoidal cross-sectional shape of the protruding portion 13 has been described as a straight line, but it may have a curved shape that smoothly connects from the inner wall surface 12 of the intake passage 11. Similar effects can be expected. Further, according to this embodiment, stagnation of the intake air in the vicinity of the protruding portion 13 can be eliminated to reduce air resistance, and molding distortion of the throttle body 10 during resin integral molding can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a main configuration of an intake control device for an internal combustion engine according to a first example of an embodiment of the present invention.

FIG. 2 is a sectional view showing a modification of FIG.

FIG. 3 is a sectional view showing a configuration of a main part of an intake control device for an internal combustion engine according to a second example of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Throttle body 11 Intake path 12 Inner wall surface 13 Projection part 22 Throttle valve 31 Metal core 32 Heater member

Claims (6)

[Claims] 1. A concentric protruding portion toward a center axis of a cross section is formed on a part of an inner wall surface of an intake passage for pivotally supporting a throttle valve for adjusting an intake air amount which is an amount of air taken into an internal combustion engine. The formed throttle body made of resin, is opposed to and proximate to the periphery of the throttle valve in the vicinity of the fully closed position of the opening / closing trajectory of the throttle valve, and the surface is at least exposed to the intake passage so as to be exposed from the protrusion. An intake control device for an internal combustion engine, comprising: a buried annular metal core; and a heater member having a heater wire joined, printed, or wound along the metal core. 2. The intake control device for an internal combustion engine according to claim 1, wherein the projection has a substantially trapezoidal cross section along the direction of air flow. 3. A throttle body made of resin having an intake passage for pivotally supporting a throttle valve for adjusting an intake air amount which is an amount of air taken into the internal combustion engine, and a throttle valve of the throttle valve. An annular metal core buried in the intake passage so as to protrude and concentrically project from the inner wall surface of the intake passage toward the center axis of the cross section from the inner wall surface of the intake passage so as to be exposed near the throttle valve in the vicinity of the fully closed position; An intake control device for an internal combustion engine, comprising: a heater member formed by joining, printing, or winding a heater wire along the metal core. 4. The intake control device for an internal combustion engine according to claim 3, wherein the metal core has a substantially trapezoidal cross section along the direction of air flow. 5. The intake control device for an internal combustion engine according to claim 1, wherein the heater member is disposed on an inner wall surface, an outer wall surface, or a side wall surface of the metal core. 6. The internal combustion engine according to claim 1, wherein the throttle valve has an auxiliary member for setting a nonlinear region in which the intake air amount gradually increases near the fully closed position. Intake control device.