JPS63230931A - Intake throttle valve for engine - Google Patents

Abstract

PURPOSE:To prevent biting at fully-closed position and increase of air leakage without sacrifice of rigidity of valve plate by making a recess at a portion passing through a face which passes perpendicularly with the axis of an intake path in front edge of the valve plate. CONSTITUTION:An edge 7 at the downstream side of a valve plate 5 at the right side of a valve shaft 3 and an edge 8 at the upstream side of the valve plate 5 at the left side are positioned forward in rotary closing direction of valve. Recesses 9, 10 extending from a portion which is slightly at the inside of the outside circumferential face of the valve shaft 3, i.e. a portion which is slightly nearer to the valve shaft 3 than a cross line between the outside circumferential face and a face L-L, are made at the circumferential section of the valve plate 5 lapping over the valve shaft 3 by notching the edges 7, 8. The shape of the recesses 9, 10 is set based on the thickness of the valve plate 5 and the fully-closed angle such that the edges 7, 8 do not pass the face L-L. Consequently, biting of the valve plate 5 can be prevented while bending of valve plate due to high intake negative pressure can be reduced when the valve is closed and increase of air leakage is minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle valve for controlling the intake air amount of a motor/engine, and is mainly used for a vehicle engine.

Vaporizer for liquid fuel, mixer 8i for gaseous fuel to control machine/gin rotation speed.

It is well known that a throttle valve is installed to control the increase and decrease of the intake air volume in the throttle body trap in the fuel injection system.The throttle valve is operated by the foot or hand of a general VCl 4 user. The valve stem is placed across the center of the intake passage, and the valve body is rotated arbitrarily between fully closed and fully open to control the amount of intake air.In other words, the intake cover changes depending on the rotation angle of the valve stem. Although it changes,
If the intake passage diameter is large relative to the engine displacement, when the throttle valve is slightly opened from the idle position and the vehicle is started, the ratio of the intake air volume tank 7100 to the valve shaft rotation angle is large, so the engine rotation speed will be higher than necessary. Become. Therefore.

In the low opening range of the crest valve, the intake air amount tank 7 relative to the valve shaft rotation angle
Although it is preferable to reduce the ratio of Jkl, since the intake passage diameter is determined by the maximum output, it cannot be reduced beyond a certain level.

Therefore, it has been considered to reduce the rate of increase in intake air filtration by reducing the fully closed angle of the throttle valve, that is, the angle of the valve plate with respect to the plane perpendicular to the axis of the intake passage. The valve plate may bite into the wall of the intake passage, causing malfunction. In particular, in the case of a valve plate that is made thicker and more rigid in order to eliminate bending due to suction negative pressure, it is likely that galling will occur adjacent to the area where it overlaps with the valve stem.

FIG. 7 is a diagram illustrating the bite, in which the plane L-L, which is the central axis of the intake passage and passes through the central axis of the valve shaft S at the angle When the front edge passes in the direction of rotation, a bite occurs in this passing portion. This section A~B and C~
It is understood from the figure that D changes depending on the diameter of the valve stem S, the thickness t of the valve plate V, and the fully closed angle θ, and that the larger t is or the smaller θ is, the longer it becomes.

As a countermeasure, for example, as shown in Fig. 8.9, the valve plate V
At the peripheral edge portion of the side that overlaps with the valve stem S, a recessed portion G that is open to the outer circumferential surface on the downstream side is provided by cutting or the like through the overlapped portion with the valve stem S, and the sections A to B in Fig. 7 are the surface L. -L
Attempts are being made to make it more upstream than the above.

However, as mentioned above (by providing the bulge G, the valve shaft S
If a relief is formed in the peripheral edge part of the side that overlaps with the A-B section at the fully closed position, there will be no gap in this part, but since the wall is thin, it will be bent by the suction negative and positive, causing air leakage. If the amount is increased, the idle rotational speed becomes higher than necessary, which not only causes inconveniences such as work/engine/noise and wasted fuel, but also makes it impossible to prevent the sluggishness in the two sections C to D. As a countermeasure, cut off the periphery from both sides.

Furthermore, the wall becomes thinner, and air leakage and mold increase significantly.

SUMMARY OF THE INVENTION Therefore, the present invention provides an intake throttle valve for an engine that does not cause the valve plate to lose its rigidity, does not cause jamming in the fully closed position, does not increase the amount of air leakage, and also allows the fully closed angle to be set to a small value. .

In the present invention, a recessed portion open to the outer circumferential surface is formed in a peripheral edge portion of the valve plate on the side that overlaps with the valve shaft, which is peered into the valve shaft disposed across the intake passage, and the recessed portion is Extending from a little inside to the outside of the outer peripheral surface of the valve shaft.

and a configuration provided at a portion of the front edge of the valve plate in the direction of valve closing movement that passes through a plane that is perpendicular to the central axis of the intake passage and passes through the central axis of the valve shaft. When the throttle valve closes from the open position, it passes through a plane that is perpendicular to the center axis of the intake passage and passes through the center axis of the valve shaft. According to the present invention, the edge that passes through the plane passing through the central axis of the valve stem is retracted to a position where it does not pass through the valve stem because it does not exist on the valve plate due to the recess. This eliminates the phenomenon of the portion of the valve plate adjacent to the portion overlapping the valve shaft biting into the wall of the intake passage. Even if it is made within the thickness of the valve plate (choking can be prevented by appropriately selecting the thickness of the recessed part, and the recessed part extends from slightly inside to the outside of the outer peripheral surface of the valve shaft). Since the valve stem does not cross the valve stem, it is possible to reduce bending due to high suction negative pressure when the valve is closed, minimize the increase in air leakage, and prevent noise and fuel waste when the engine is idling. Furthermore, by appropriately selecting the length of the recessed portion, it is possible to reduce the fully closed angle and thereby improve engine drivability in a low speed rotation range.

Embodiment 1.2.3 shows a first embodiment of the present invention, in which a valve shaft 3 disposed across the center of an intake passage 2 formed in a fuselage 1 has a central axis centered on the valve shaft 3. A groove 4 is provided, and a circular valve plate S is fitted into the groove 4, and a set screw 6 is inserted.
Fixed by The valve stem 3 is generally operated by the driver's foot or hand, and the valve plate 57f! : It rotates between a fully open position parallel to the central axis @X-X of the intake passage 2 and a fully closed position.

From the fully open position, it rotates clockwise in Figure 1.2 to reach the fully closed position shown. In the fully open position, the valve @5 has a fully closed angle of θ with respect to a plane L-L that is perpendicular to the central axis X-x and passes through the central axis of the valve shaft 3.

In FIG. 1.2, the downstream edge 7 of the valve plate 5 in the right-hand part of the valve stem 3 and the valve plate 5 in the left-hand part of the valve stem 3
The upstream edge 8 of the valve is located forward in the valve closing rotation direction. and.

At the peripheral edge portion of the valve plate 5 on the side that overlaps with the valve stem 3, the valve stem 3
A concave portion 9°lO extending outward from a portion slightly inside the outer circumferential surface of the valve shaft 3 than the intersection line of the outer circumferential surface and the surface L-L is the edge 7, It is provided by cutting out 8.

These recesses 9 and 10 are formed by cutting or pressing, and their thickness in the valve thickness direction and length in the valve plate direction are such that in the fully closed position, the edges 7 and 8 are L-
The thickness of the valve plate 5 and the full closing angle are set so that the valve plate 5 does not pass through L.

FIG. 4 shows a second embodiment of the present invention, in which the valve plate 5, which is fitted and fixed in the groove 4 of the valve stem 3, is oriented in the direction of valve-closing rotation as in the first embodiment. There are recesses 9 in the front edges 7 and 8. Similar recesses 13 and 14 are also provided on the rear edges 11 and 12 in the direction of valve closing rotation. Since the valve plate 5 of this embodiment is symmetrical on both sides, there is no need to consider directionality when assembling it to the valve shaft 3.

FIG. 5 shows a third embodiment of the present invention, in which a valve plate 5 is fitted and fixed from the downstream side of the intake passage into a notch pII15 formed by cutting on the diameter of the valve shaft 3, and the valve plate 5 is fixedly closed. In the direction of valve rotation - [the downstream end of the valve plate 5 in the right-hand portion of the valve shaft 3 in the figure, which passes through the same face when the valve is rotated in the valve-closing direction among the edges located in the front. A concave portion 16 is provided on the edge 7.

No. 611 shows a fourth embodiment of the present invention, in which a valve plate 5 is fitted and fixed from the upstream side of the intake passage into a cut groove 17 formed by cutting on the diameter of the valve shaft 3. An edge 8 on the upstream side of the valve plate 5 at the left side portion of the valve shaft 3 in the figure, which passes over the same surface when rotating in the valve closing direction among the edges located forward in the valve rotation direction. A recessed portion 18 is provided therein.

It is the same as in the first and second embodiments that the thickness and length of the recessed portions 16 and 18 of the third and fourth embodiments are set according to the thickness of the valve plate 5 and the fully closed angle. These hollows 9
, 10, 13, 14, 16° 18 eliminates the bite when fully closed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention. FIG. 2 is an enlarged partial view of FIG. 1, FIG. 3 is a plan view of FIG. 1, and FIGS. 4, 5, and 6 are enlarged views of second, third, and fourth embodiments of the present invention. Partial view. FIG. 7 is a diagram for explaining the biting, FIG. 8 is a front view of a conventional example, and FIG. 9 is a plan view of FIG. 8. 3... Valve shaft, 5... Valve plate, 7.8...
...Edge. 9.10.13, 14, 16.18...-Kuhomi Department.

Claims (1)

[Scope of Claims] A recessed portion open to the outer circumferential surface is formed in the peripheral edge portion of the valve plate attached to the valve shaft disposed across the intake passage on the side that overlaps with the valve shaft, and the recessed portion opens to the outer circumferential surface. The portion extends from a little inside to the outside of the outer peripheral surface of the valve shaft, and is perpendicular to the central axis of the intake passage within the front edge of the valve plate in the valve closing rotation direction. An intake throttle valve for an engine, characterized in that it is provided at a portion passing through a plane passing through the center axis of the valve shaft.