JPH07279696A - Throttle valve - Google Patents

Abstract

PURPOSE:To enable the airtight state in full closing to be kept even if the dimensional precision of a throttle valve body is made rough. CONSTITUTION:Hemispherical projecting lines 7a, 7b are so provided as to extending from upper and lower intake passage walls of a valve shaft 2 to the intake passage center direction. Rubber seal members 8, 8 are fixed in the position to face the projecting streaks 7b, 7b of a plate valve 1. Projecting streaks are provided on the rubber seal members 8 and so arranged as to be brought in light-contact with the projecting streaks of the intake passage in a state where the projecting streak is inclined in the full closed position of the plate valve 1. These projecting streaks receive moment by pressure difference between the upstream and the downstream of the intake passage and is brought in pressure-contact with the projecting streak 7b, 7b of the intake passage, thereby airtightness of the plate valve 1 is secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve for an automobile engine, and more particularly to a throttle valve which can obtain a good shutoff performance without increasing the dimensional accuracy of a throttle body.

[0002]

2. Description of the Related Art An example of a conventional throttle valve for an automobile engine is shown in FIG. Although the throttle body is not shown in the figure, an intake passage 7a is formed in the throttle body, and the plate valve 1 for opening and closing the intake passage 7a is fixed to the valve shaft 2. The valve shaft 2 is rotatably supported by a bearing provided on the throttle body, and the coil spring 3
Is urged in the valve closing direction by.

An accelerator lever 4 is fixedly attached to the valve shaft 2, and a wire 5 connected to an accelerator pedal is wound around an arc portion of a peripheral edge thereof. Further, the adjusting screw 6 is screwed into a screw hole provided in the boss 7e of the throttle body so as to come into contact with the bent portion of the accelerator lever 4. When the accelerator pedal is depressed, the plate valve 1 is opened via the wire 5, and when the accelerator pedal is released, the plate valve 1 is rotated by the elastic force of the coil spring 3 in the closing direction shown in the drawing. It is regulated by the adjusting screw 6.

FIG. 5 shows a state where the plate valve 1 is fully closed. The plate valve 1 is stopped at a position forming an angle θ with respect to the direction perpendicular to the intake passage wall. The stop position is set by the adjusting screw 6 described above. When the plate valve 1 comes into contact with the intake passage 7a of the throttle body and stops before the adjusting screw 6 and the accelerator lever 4 come into contact with each other, the angle θ is set.
Since the pressure is small, the pressure contact force between the intake passage 7a and the plate valve 1 becomes very large, and there is a possibility that a stick state (adhered state) may occur due to the adhesion of carbon or oil mist.

Therefore, the intake passage 7a and the plate valve 1 are fully closed.
The position of the adjusting screw 6 is set so that and are slightly apart,
Even when the throttle valve is fully closed, air is allowed to flow through the throttle valve. When the throttle valve is fully closed, that is, when the engine is idle, intake air is mainly supplied by the idle speed adjusting valve provided in the bypass passage, but as described above, it is also supplied from the throttle valve, and the amount of air flowing through the throttle valve depends on the shape of the throttle valve. It is easy to change due to
There was a problem that the intake amount in the engine idle state became unstable.

As shown in FIG. 6, the throttle valve disclosed in Japanese Patent Laid-Open No. 5-171960 has a ridge 7 in the intake passage 7a.
b and 7b are provided, and the plate valve 1 is brought into contact with the ridges 7b and 7b to be fully closed. In this case, the plate valve 1 moves vertically with respect to the ridges 7b, 7b, so that the pressure contact force is small and it is difficult to form a stick state. However, since the plate valve 1 and the ridge 7b are rigid bodies, they are airtight over the entire circumference. It is difficult to keep the temperature in manufacturing due to accuracy and thermal deformation, and there is a problem that air leakage occurs in the fully closed state.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to maintain an airtight state when fully closed even when the dimensional accuracy of the throttle body is roughened. Is to provide a throttle valve that can.

Another object of the present invention is to provide a throttle valve in which the plate valve does not get stuck in the fully closed state.

Still another object of the present invention is to provide a throttle valve capable of stabilizing the engine idle speed by supplying a total amount of intake air from the idle speed adjusting valve in the engine idle state.

[0010]

In the throttle valve of the present invention, a plate valve is fixed to a valve shaft that traverses an intake passage, and the intake passage is opened and closed by the rotation of the valve shaft to open and close the fully closed position of the plate valve. In a throttle valve that is set with a stopper that restricts rotation of the shaft and has an idle speed adjustment valve in a bypass passage that bypasses the plate valve, a half valve from the intake passage wall is close to the plate valve when the plate valve is fully closed. Extend a circular ridge, and fix a rubber seal member that has a ridge extending toward the ridge at a position facing the ridge of the plate valve, and when the plate valve is fully closed, the upstream side and the downstream side of the intake passage The ridge of the rubber seal member is pressed against the ridge of the intake passage due to a pressure difference between the ridge and the ridge.

In the throttle valve, a resin material is used for the throttle body forming the intake passage.

Further, in each of the throttle valves, heating means is arranged near the idle speed adjusting valve.

[0013]

According to the throttle valve of the present invention, the ridges of the rubber seal member fixed to the plate valve are in contact with the ridges of the intake passage when fully closed, and the pressure difference between the upstream side and the downstream side causes the rubber seal member to move. The ridge is pressed against the ridge of the intake passage. Further, since the rubber is easily deformed, even if the shape of the throttle body varies, the ridge of the rubber closely contacts the ridge of the intake passage to keep airtightness.

Further, the throttle valve is set in its fully closed position by a stopper for restricting the rotation of the valve shaft. However, since the throttle valve moves in the direction perpendicular to the ridge of the intake passage, the dimensional accuracy cannot be improved. Even if the throttle valve is fully closed, the ridges of the rubber seal member can be lightly contacted with the ridges of the intake passage. In this way, the rubber ridge is pressed against the ridge of the intake passage due to the pressure difference of the intake air, but since the pressure is limited, no sticking occurs.

In the engine idle state, the total amount of intake air flows to the idle speed adjusting valve, the amount is stabilized, and the idle speed is also stabilized. Then, since the intake throttle is generated and the temperature is lowered only in the idle speed adjusting valve, icing (freezing) can be prevented only by heating the idle speed adjusting valve.

Since it is not necessary to increase the dimensional accuracy of the throttle body as described above, it is possible to use a molded product made of a resin material that changes in size with temperature and is easily deformed by an external force as it is, resulting in a large manufacturing cost. Reduced to.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A throttle valve which is an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a throttle valve that is an embodiment of the present invention. In the figure, 7 is a resin throttle body, and the intake passage 7 is provided on the inner surface thereof.
a is formed. Plate valve 1 for opening and closing the intake passage 7a
Is fixed to the valve shaft 2. The valve shaft 2 is rotatably supported by a bearing provided on the throttle body, and is urged in the valve closing direction by a coil spring like the throttle valve shown in FIG. 4, though not shown.

Further, an accelerator lever is fixed to the valve shaft 2, the plate valve 1 is opened and closed by an accelerator petal, and its fully closed position is set by an adjusting screw provided on the throttle body, as shown in FIG. It is similar to the throttle valve shown.

Air flows in the intake passage 7a from the left to the right as shown by the arrow in the figure. Semicircular ridges 7b extending from the upper and lower intake passage walls of the valve shaft 2 toward the center of the intake passage,
7b is provided. These ridges 7b, 7b are arranged such that the upper part of the valve shaft 2 is located downstream of the plate valve 1 and the lower part of the valve shaft 2 is located upstream of the plate valve 1. Rubber seal members 8, 8 are fixed to the plate valve 1 at positions facing the ridges 7b, 7b by baking or bonding. A front view of the plate valve 1 is shown in FIG.

The parts A and B of FIG. 1 are shown in detail in FIGS. 2A and 2B, respectively. As shown in the figure, the rubber seal member 8 is provided with a ridge 8a,
At the fully closed position of the plate valve 1, the ridges 8a are arranged so as to be in contact with the ridges 7b of the intake passage in an inclined state. These ridges 8a, 8a receive a moment in the direction indicated by the arrow due to the pressure difference between the upstream side and the downstream side of the intake passage, and are pressed against the ridges 7b, 7b of the intake passage to ensure the airtightness of the plate valve 1.

The throttle body 7 is provided with a bypass passage 7c for bypassing the plate valve 1, and an idle speed adjusting valve 9 for adjusting the amount of air flowing through the bypass passage 7c is screwed into the throttle body 7. When the plate valve 1 is fully closed, that is, in the engine idle state, the plate valve 1 closes the intake passage 7a and the intake air passes through the bypass passage 7c, but the amount thereof is accurately set by the idle speed adjusting valve 9.

In the engine idle state, the air flow is throttled by the idle speed adjusting valve 9 to lower the temperature, but the hot water passage 7d provided in the vicinity of the idle speed adjusting valve 9
By flowing hot water to the vicinity of the idle speed adjusting valve 9, the icing is prevented.

[0023]

As described above, according to the throttle valve of the present invention, the ridges of the rubber seal member fixed to the plate valve are in contact with the ridges of the intake passage when the throttle valve is fully closed. The ridge of the rubber seal member is pressed against the ridge of the intake passage due to the pressure difference between the ridge and the ridge. Further, since the rubber is easily deformed, even if the shape of the throttle body varies, the ridge of the rubber closely contacts the ridge of the intake passage to keep airtightness.

Further, the throttle valve is set in its fully closed position by a stopper for restricting the rotation of the valve shaft. However, the throttle valve moves in a direction perpendicular to the ridge of the intake passage, so that the dimensional accuracy is not improved. Even if the throttle valve is fully closed, the ridges of the rubber seal member can be lightly contacted with the ridges of the intake passage. In this way, the rubber ridge is pressed against the ridge of the intake passage due to the pressure difference of the intake air, but since the pressure is limited, no sticking occurs.

In the engine idle state, the total amount of intake air flows to the idle speed adjusting valve, the amount is stabilized, and the idle speed is also stabilized. Then, the throttle of the intake air is generated and the temperature is lowered only in the portion of the idle speed adjusting valve, so that the icing can be prevented only by heating the idle speed adjusting valve.

Since it is not necessary to increase the dimensional accuracy of the throttle body, it is possible to use a molded product made of a resin material, the size of which changes with temperature and which is easily deformed by an external force, so that the manufacturing cost is greatly reduced. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a throttle valve that is an embodiment of the present invention.

FIG. 2 (A) is a detailed view showing a portion A in FIG.
FIG. 2B is a detailed view showing the B section in FIG.

FIG. 3 is a front view showing a plate valve of the throttle valve.

FIG. 4 is a perspective view showing an example of a conventional throttle valve.

FIG. 5 is a cross-sectional view showing a closed state of the throttle valve.

FIG. 6 is a cross-sectional view showing another example of a conventional throttle valve.

[Explanation of symbols]

1 plate valve 2 valve shaft 3 coil spring 4 accelerator lever 5 wire 6 adjusting screw 7 throttle body, 7a intake passage, 7b convex line,
7c Bypass passage 7d Hot water passage, 7e Boss 8 Rubber seal member, 8a Projection 9 Idle speed adjustment valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02M 31/04 A 35/10

Claims (3)

[Claims] 1. A plate valve is fixed to a valve shaft that traverses an intake passage, the intake passage is opened and closed by the rotation of the valve shaft, and the fully closed position of the plate valve is set by a stopper that restricts the rotation of the valve shaft. With the throttle valve provided with an idle speed adjusting valve in the bypass passage that bypasses the plate valve, a semicircular ridge is extended from the intake passage wall to a position where the plate valve approaches when the plate valve is fully closed. A rubber seal member having a ridge extending toward the ridge is fixed at a position facing the ridge, and the ridge of the rubber seal member is caused by the pressure difference between the upstream side and the downstream side of the intake passage when the plate valve is fully closed. A throttle valve configured to be pressed against the ridge of the intake passage. 2. The throttle valve according to claim 1, wherein a resin material is used for the throttle body forming the intake passage. 3. The throttle valve according to claim 1, wherein a heating means is arranged near the idle speed adjusting valve.