WO2001077505A1

WO2001077505A1 - Throttle valve

Info

Publication number: WO2001077505A1
Application number: PCT/JP2001/002831
Authority: WO
Inventors: Toshio Karasawa; Hirofumi Asakura; Younosuke Hatsumi
Original assignee: Mikuni Corporation
Priority date: 2000-04-05
Filing date: 2001-03-30
Publication date: 2001-10-18
Also published as: JP2001289070A

Abstract

A throttle valve (10) disposed in a cylindrical bore (2) so as to cross the center axis of the bore and supported rotatably by a throttle shaft passing through the bore, wherein a bitten zone (10a) (diagonally shaded area) on the external surface of the throttle valve (10) near the area crossing the throttle shaft is removed by cutting so as to avoid an interference with the bore (2), and the maximum value δ max of a recess is shown by the expression (2); instead of forming such a recess, height differences (20b) and (20c) may be formed as shown in Fig. 3 or a thick wall part (30b) may be formed as shown in Fig. 4, whereby an increase in intake air volume at the time when the valve is fully closed and in a small opening area of the valve can be suppressed.

Description

Description Throttle valve Technical field

The present invention relates to a throttle valve used for a throttle body, and more particularly, to a throttle valve capable of reducing a totally closed leak amount and a change in air flow rate in a low opening region of the throttle valve. Background art

In a fuel supply system for an automobile gasoline engine, fuel and air are separately controlled, and are electronically controlled so as to achieve a required air-fuel ratio. The amount of air is controlled by a throttle valve, but it is desirable that the diameter of the throttle pod be as large as possible to improve the engine output.

FIG. 5 is a diagram showing a relationship between the opening degree (angle) of the throttle valve and the intake air amount. In the figure, when the throttle valve is fully closed, the intake air volume is not zero. This is because if it is set to 0 when fully closed, the throttle valve and the pore will come into close contact, and if they are brought into close contact, the valve will be more likely to bite into the pore, making it impossible to open and close the valve. However, this is because a small gap is kept between the valve and the pore. Normally, the idling opening is set at a position slightly opened from the fully closed position.

When the throttle valve starts to open from the idling position, the increase in the amount of intake air is small in the small opening range, and suddenly increases when the opening increases. To rise. It is desired that the slope (angle) of the tangent at the time of idling of this curve be made as small as possible so that the change in the amount of intake air when the valve starts to open from the idling state.

This is done for the following reasons. The throttle valve opening is determined by the accelerator pedal depression amount. This needs to be prevented so that the vehicle can be launched at a safe speed. Therefore, it is very important that the angle α is small. In recent years, efforts have been made to minimize the engine speed during idling in order to reduce fuel consumption and silence. Therefore, it is important to be able to finely control the amount of air before and after the idling opening.

FIG. 6 is a view showing a conventional throttle valve. A disk-shaped throttle valve 1 is disposed in a cylindrical bore 2 so as to intersect with the central axis a of the bore 2 and is fixed to a throttle shaft (not shown) penetrating the bore with screws or the like. It is mounted to be rotatable around the shaft の of the torque shaft.

Conventionally, to reduce the angle α,

(1) Reduce the fully closed angle of the throttle valve 1 shown in Fig. 6 and increase the plate thickness t to make the change in the air amount in the low opening range close to the required value.

(2) Set the fully closed angle S to 0. For this purpose, a perfect circular valve whose outer peripheral surface is a spherical surface with a diameter approximately equal to the pore diameter is adopted.

(3) Change the accelerator wire lever ratio to reduce the change in the amount of air in the low opening range.

(4) Correspondence with spherical pore and spherical valve. And other measures have been adopted.

Among the above countermeasures, the measures to reduce the angle when fully closed in (1) and to increase the thickness t are relatively simple in configuration and have little effect on cost. Measures are often adopted.

By the way, pulp 1 usually has a disk shape, but since the gap s between the valve 1 and the pore 2 is small, if the thickness t of the valve 1 is increased, the pulp rotates in the direction of the arrow shown in Fig. 6. In this case, the cross-hatched portion 1a in FIG. 6 on the outer peripheral surface of the pulp theoretically interferes with the pore 2. This part of l a is referred to here as the “consolidation zone”. The penetration zone is perpendicular to the line a '(which overlaps with the line a in Fig. 6) which passes through the point of intersection with the rotation axis 0 on the outer peripheral surface of the valve 1 and is parallel to the central axis a. And a line b drawn along the outer periphery of the valve 1 so as to pass through the rotation 0 and the rotation 0.

Therefore, the gap s between the valve 1 and the pore 2 is increased so that the penetration zone 1a does not interfere with the bore. For this reason, there has been a problem that the amount of intake air when fully closed and when idling increases, and the angle α inevitably increases.

The present invention has been made in order to solve the above problems, and has as its object to provide a throttle valve capable of reducing an increase in the amount of intake air when the valve is fully closed and in a low opening range. Disclosure of the invention

A throttle valve according to the present invention is arranged in a cylindrical bore so as to intersect with the center axis of the bore, and is rotatably supported by a throttle shaft passing through the bore. The penetration zone near the intersection with the throttle shaft is It is characterized by being escaped so as to avoid interference.

It is preferable that the penetration zone is located inside a spherical surface centered on the center point of the valve and having a diameter equal to the diameter of the valve.

Or a disk-shaped throttle valve that is disposed in a cylindrical bore so as to intersect with the center axis of the bore and is rotatably supported by a throttle shaft that penetrates the bore; The thickness is divided into two parts by a plane including the rotation axis, and a semicircular step is formed on one side of the throttle shaft on the front side and a semicircular step on the other side of the throttle shaft. It is characterized by being formed.

It is possible to adopt a configuration in which the step portion enters the inside of a spherical surface having the diameter of the pulp centered on the center point of the valve.

Alternatively, a disc-shaped throttle valve arranged in a cylindrical bore so as to intersect with the center axis of the bore and rotatably supported by a throttle shaft penetrating the bore, The thickness is divided into two parts by a plane including the rotation axis, and the rear part in the direction of rotation of the valve of one of the two parts of the thickness of the throttle shaft is the thick part, and the outer diameter of the thick part The outer peripheral surface of the thick portion is located inside a spherical surface centered on the center point of the valve and having a diameter equal to the diameter of the valve. I have. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a valve according to a first embodiment of the present invention.

FIG. 2 is an Xz plan view at y = 0 in FIG.

FIG. 3 shows a second embodiment of the present invention.

FIG. 4 is a side view of a valve according to a third embodiment of the present invention.

Fig. 5 is a diagram showing the relationship between the throttle valve opening and the amount of intake air. is there.

FIG. 6 is a diagram of a conventional throttle valve, and is a diagram for explaining a penetration zone. '' Best mode for carrying out the invention

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a valve according to a first embodiment of the present invention. In the figure, a valve 10 is located in a bore 2 and is rotatably mounted by a throttle shaft (not shown). The X axis in the figure overlaps with the axis of the throttle shaft, and the z axis overlaps with the center axis of bore 2. The y-axis is an axis that is orthogonal to both the X-axis and the z-axis. And point 0 'is the intersection of the X, y, and z axes, which is the center point of the valve 10.

In FIG. 1, the lines a ′ and b that define the embedding zone 10a are the same as those described in FIG. Assuming that the gap between valve 10 and bore 2 is s, s = 0, and in order to prevent galling between valve 1 and bore 2, the penetration zone 1 of valve 10 must be As shown in Fig. 1, the portion of 0a was gradually increased toward the outer peripheral edge of the valve at 0 on line b, and was cut off so that the maximum dmax was reached at the intersection of line a 'and the outer peripheral edge of the valve. It is necessary to form it into a shape with relief. That is, the penetration zone 10a of the valve 10 in FIG. 1 is released so as to enter the inside of the sphere having the diameter Dv of the valve 10 centered on the point 〇 '. In other words, the distance r from point 〇 'to any point in the penetration zone 10a is

'r <(Dv / 2) (1)

I am trying to be.

Then, the maximum relief amount <5 max at the outer peripheral edge of the valve based on the equation (1) can be obtained as follows from FIG. Incorporation zone 1 0 The shape of a may be a slope, but if the shape is a sphere, the gap between the bore 2 and the valve 10 approaches a constant, and the angle α can be reduced.

FIG. 2 is a cross-sectional view of the pulp 10 at y = 0 on the ζ-X plane. Then, set the angle of the knob when fully closed (the angle corresponding to Θ in Fig. 6). If the plate thickness of the valve 10 = t, and r (D v / 2), then:

From the above equation (1)

[Equation 2]

Becomes

Generally, t = l ~ 4mm,. = 0 to 20 °, diameter of valve 10 D v = pore diameter Db = 20 to 80 mm

<5max> 0.003 to 0.229 mm

Becomes The minimum value of 0.003mm is t = l,. = 0 °, Db 80mm, maximum value 0.229mm, t = 4mm,. = 20 ° and D b = 20 mm.

From the above, if the penetration zone 10a is made smaller than the bulb diameter Dv, the valve will not stick to the pore even if the gap s between the pulp and the bore is s = 0. become.

Also, after incorporating a valve in the slot Torubodi, easily coated with paint and M0 ₂ in removing the meat has been part of the zone part narrowing seen嚙, difficult to peel off (solid This makes it possible to further improve the fully closed position and finely control the air volume before and after the idling opening.

FIG. 3 is a view showing a valve according to a second embodiment of the present invention. In this embodiment, the thickness of the valve 20 is divided into two sides by a plane c passing through the center axis of the throttle shaft and parallel to the disk of the valve, and the rotation direction of the valve 20 is divided into two. (5 max is a value obtained from the above equations (1) and (2). In addition, the diameter D v of the valve 20 is Is approximately the same size as the bore diameter D b.

As shown in FIG. 3 (b), the pulp 20 has a state in which a semi-circular step is formed in the thickness direction, and one of the upper and lower sides of the valve has a semi-circular step 20 formed in the front half. The other of the upper and lower sides has a semicircular step 20c formed in the back half. Conventionally, the radius of the entire thickness of the valve 20 was reduced by ό max. However, in the present invention, the gap between the bore and the bore is limited to <5 max for only about 1 to 2 of the valve thickness. In the remaining part, the gap between the bore and the bore was almost zero, so that the gap between the valve and the bore could be significantly reduced. With this configuration, even if the valve 20 rotates in the direction of the arrow in FIG. 4, the entire valve 20 including the penetration zone 20a can be prevented from penetrating into the bore. The tightness of the large-diameter part with the seal is improved, the amount of air when fully closed is reduced, and the flow gradient in the low opening region can be reduced. In the embodiment of FIG. 3, in consideration of the thickness of the throttle shaft 21, a relief is provided for a portion 20 a ′ overlapping with the throttle shaft 21 in the recessed zone 20 a. No need. Therefore, it is not necessary to hit the bore even if 20a is included except for 20a '. That is, considering the thickness of the throttle shaft, the amount of the step (5 can be made smaller than dmax, and the flow gradient in the low opening region can be further reduced. Escape to the part overlapping with the throttle shaft The non-forming is also applicable in the embodiment of FIG.

Comparing the embodiment of FIG. 1 with the embodiment of FIG. 3, the embodiment of FIG. 1 has a smaller leakage amount when fully closed, but is difficult to machine, and the embodiment of FIG. It is easy to process and easy to mold.

FIG. 4 is a view showing a valve according to a third embodiment of the present invention. The valve 30 in the figure is configured to rotate and open in the direction of the arrow. In this embodiment, the shape of the lower portion of the pulp 30 is the same as that of the embodiment of FIG. 3, and a step 30a is formed behind the pulp 30 in the rotation direction, but the upper half is A thick plate portion 30b is formed, and an outer peripheral surface 30c of the thick plate portion 30b facing the bore is formed in an arc shape. The thick plate portion 3 Ob has a gradient such that it is thickest around the valve 30 and becomes thinner toward the center.

In addition, the amount of the step <5 on the outer peripheral surface 30c can be made smaller than δmax in consideration of the thickness of the throttle shaft 31. In addition, since the thickness of the valve is increased in the upper half of the valve, the air flow rate when the valve is fully closed can be reduced, and the increase in the amount of intake air in the low opening region of the throttle valve can be reduced.

In this embodiment, the upper and lower portions of the valve cannot be symmetrical. This is because when the valve 30 rotates in the direction of the arrow, the upper side can rotate without any problem, but the lower side interferes with the pores and cannot rotate. Industrial applicability

A throttle valve according to the present invention is arranged in a cylindrical bore so as to intersect with a center axis of the bore, and is rotatably supported by a throttle shaft passing through the bore. Since the penetration zone near the crossing with the throttle shaft is escaped to avoid interference with the bore, the throttle valve The gap between the bore and the bore can be minimized, the amount of air leakage when fully closed is minimized, and the increase in engine speed in the low opening range can be moderated.

If a relief is not formed in a portion of the outer periphery of the pulp overlapping the throttle shaft, the amount of relief can be reduced, and the amount of intake air when fully closed can be reduced.

Alternatively, a disc-shaped throttle valve is disposed in a cylindrical pore so as to intersect with the center axis of the pore, and is rotatably supported by a throttle shaft penetrating the bore. The thickness is divided into two parts by the plane including the rotation axis to form a semicircular step on the front side on one side of the throttle shaft, and a semicircular step on the back side on the other side of the throttle shaft. Due to the configuration, the gap between the throttle valve and the bore can be reduced with a relatively simple configuration.

Or a disc-shaped throttle valve disposed in a cylindrical bore so as to intersect the center axis of the bore and rotatably supported by a throttle shaft passing through the bore, The thickness of the valve is divided into two parts on the plane including the rotation axis, and the thickness of the one side of the throttle shaft is defined as the thick part on the rear side in the direction of rotation of the valve. If the diameter is made smaller than the outer diameter on the front side in the rotation direction to provide a step, and the outer peripheral surface of the thick portion is located inside the spherical surface having the diameter of the valve centered on the center point of the valve. The gap between the throttle pulp and the pore can be smaller than that described above.

Claims

The scope of the claims

1. A throttle valve which is disposed in a cylindrical bore so as to intersect with the center axis of the bore and is rotatably supported by a throttle shaft passing through the bore, wherein the throttle shaft on the outer peripheral surface of the throttle pulp is provided. The throttle valve is characterized in that the penetration zone near the intersection with the gate is vented to avoid interference with the pore.

2. The throttle valve according to claim 1, wherein the recessed zone is located inside a spherical surface having the diameter of the valve centered on the center point of the valve.

3. The throttle valve according to claim 1, wherein no relief is formed in a portion of the outer periphery of the valve that overlaps the throttle shaft.

4. A disk-shaped throttle valve which is disposed in a cylindrical bore so as to intersect with the central axis of the bore and is rotatably supported by a throttle shaft passing through the bore. The thickness of the throttle valve is divided into two parts by a plane including the rotation axis, and a semicircular step is formed on one side of the throttle shaft on the front side and a semicircular step on the other side of the throttle shaft. A throttle valve characterized in that a throttle valve is formed.

5. The throttle valve according to claim 4, wherein said stepped portion enters inside a spherical surface having a diameter of a valve centered on a center point of the valve.

6. A disk-shaped throttle valve which is disposed in a cylindrical bore so as to intersect with the center axis of the bore, and is rotatably supported by a throttle shaft passing through the bore. The thickness is divided into two parts by a plane including the rotation axis, and the rear side in the direction of rotation of the valve of the two divided thicknesses on one side of the throttle shaft is a thick part, and the outer diameter of the thick part is , Times A step formed to be smaller than the outer diameter on the front side in the rolling direction, and wherein the outer peripheral surface of the thick portion is located inside a spherical surface having the diameter of the valve centered on the center point of the valve. .