JPS58214071A - Batterfly type throttle valve - Google Patents

Abstract

PURPOSE:To control the rate of flow accurately and with a simple construction by arranging a recess in the body of a batterfly throttle valve in a location near the position of valve opening and by changing the area of opening of the flow passage proportionally to the amount of turning of the throttle valve. CONSTITUTION:A square batterfly throttle valve 2 is supported rotatably around a shaft by the body 1, which has square flow passage. Because a recess 3 is provided in the body 1 of this throttle valve 2 in a location near the position in the valve opening direction, the area of opening of the flow passage changes proportionally to the amount of turning of the throttle valve 2. Provision of a displacement meter or a motor on the shaft 4 of the throttle valve 2 will make it possible to perform simple and accurate proportional control of the rate of flow using a digital computer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is mainly used as an air amount control valve for controlling the air-fuel ratio of a mixture supplied from a throttle opening sensor of an electronic fuel injection device of an internal combustion engine or a carburetor to an internal combustion engine. f'': Regarding the butterfly throttle valve device used.

Conventional butterfly type throttle valve device (for example, Japanese Patent Publication No. 52-196
30. ) is explained with reference to FIGS. 1 to 3. A body 1 having an angular flow path is provided with an angular butterfly-shaped throttle valve 2 rotatably supported by a shaft 4. The flow rate of fluid passing through the body I was controlled by changing the opening area of the flow path by rotating the valve.

In the field of internal combustion engines, a throttle is connected to the shaft 4 of a butterfly throttle valve, and a displacement 71 is attached to the shaft 4 to detect the air flow rate supplied to the engine.
The butterfly-shaped throttle valve is used as a throttle opening sensor, and also discriminates the signal from the oxygen concentration sensor installed in the exhaust system and inputs it into the computer1. A pulse motor attached to the shaft 4 of the engine was driven by a computer and was used as an air amount control valve to precisely control the air-fuel ratio supplied to the internal combustion engine.

In such a conventional butterfly-shaped throttle valve device, as shown by the solid line in FIG. 4, the flow rate does not change proportionally to the throttle valve opening, and the flow rate does not change proportionally to the throttle valve opening. − It is not possible to control the flow rate proportional to the input to the
When the output is output, the flow rate control is not proportional to the human output, which has the disadvantage that the air-fuel ratio of the internal combustion engine cannot be accurately controlled. In order to solve this problem, it has been proposed to separately provide a flow meter correction conversion circuit or device for the throttle valve opening, but these are complicated and expensive.

The present invention was proposed to improve these drawbacks, and its purpose is to provide an inexpensive butterfly throttle valve device that can change the opening area of the flow path proportionally to the amount of rotation of the butterfly throttle valve. In addition, it is an object of the present invention to provide a butterfly type throttle valve device which can be equipped with a displacement meter to perform control proportional to the flow rate, and can also be equipped with an electric motor to perform control proportional to the flow rate.

An embodiment of the present invention will be explained with reference to FIGS. 5 and 6.
A rectangular butterfly-shaped throttle valve 2 (same as shown in Fig. 3) with a shaft 4 rotatably supported is disposed in a body 1 having a rectangular flow path, and the flow is controlled by rotation of the butterfly-shaped throttle valve. The flow rate of fluid passing through the body 1 is controlled by changing the opening area of the passage.

Since both the body 1 and the butterfly-shaped throttle valve have angular shapes on both sides on which the shaft 4 is pivotally supported, the rotation of the butterfly-shaped throttle valve only causes the both sides to slide and does not affect the opening area. Therefore, the length S in the axial direction of the shaft 4 (see Figure 2), which calculates the opening area, does not change with the rotation of the throttle valve and is always constant. It is determined by multiplying the distance l between the tip of the body 1 and the inner wall surface of the body 1 by a constant S. Here, the total opening cross-sectional area of the flow path is LXS, and the opening area when the butterfly throttle valve is opened by DA as indicated by the dotted line in FIG. 5 is 2X/XS. The body near the opening direction of the butterfly throttle valve has four parts 3 so that the opening area of the flow path changes proportionally to the rotation angle of the butterfly throttle valve, that is, fO""tj'. It is located. The outline 5 of this four part 3 is (as shown in Fig. 6)
This is a contour line of an arc drawn with a radius l from the tip point A of the butterfly valve at each opening degree. In other words, the radius e from point A where the butterfly throttle valve opening is q° is given by the following formula %
Substituting di given by formula (1) sequentially from 0° to 90°, find l at each angle from the tip point A of the throttle valve, draw each arc, and the outer envelope line of those arcs is This becomes outline line 5. Next, when J = 90'', draw an arc of radius from the tip point B of the sawtooth throttle valve, and draw an arc of radius from the fixed point C on the outline 5, and the flow path becomes a fully open flow path. (between C and D).L is not necessarily the vertical length of the butterfly throttle valve.

It does not have to be the same as 2) and can be arbitrarily selected.

In this way, the outer shape 5 of the four parts 3 is formed so that the opening length corresponding to the throttle valve opening is proportional to the fully open flow path length L (according to equation (1)). Therefore, the opening area 2×lXS multiplied by the constant S changes proportionally to the butterfly throttle valve opening degree U°. For this reason, the following formula (1) % formula % (1) However, △P......Differential pressure before and after the orifice A......Opening area of the orifice C...
...Flow coefficient Q ......The differential pressure between the valve inlet and valve outlet is constant compared to the flow rate of the orifice, and the shape of the orifice hardly changes, so the flow meter coefficient is also almost constant. Then, the flow rate changes in proportion to the opening area.

Therefore, the flow rate changes in proportion to the amount of rotation of the butterfly throttle valve (as indicated by the dotted line in FIG. 4).

Note that the shape of the outer shape 5 of the fourth part 3 may be corrected according to actual experimental results, and if a displacement meter such as a potentiometer or non-contact displacement meter is attached to the shaft 4 of the butterfly throttle valve, the flow rate can be adjusted. The throttle valve opening can be directly input into a digital computer and used in an electronic fuel injection system.If an electric motor such as a pulse motor 1 reversible motor is attached to the shaft 4, the throttle valve opening can be directly input into a digital computer. The flow rate can be controlled proportionally, and the air-fuel ratio in the internal combustion engine can be controlled accurately and with high precision. Furthermore, it can be used not only in the field of internal combustion engines but also in a wide range of industrial applications as a valve device that directly controls various fluids using a digital computer. In addition, body 1
can be easily manufactured by die casting, casting, resin molding, etc.

As described above in detail, the present invention comprises a body 1 having an angular flow path and an angular butterfly-shaped throttle valve 2 rotatably supported by the body. In a butterfly type throttle valve device that changes the opening area of the flow path by rotation, the four parts 3 are arranged on the body near the opening direction of the butterfly type throttle valve, and the opening area of the flow path is proportional to the amount of rotation of the butterfly type throttle valve. Since the opening of the butterfly throttle valve changes proportionally to the flow rate, the flow rate can be changed proportionally even when a displacement meter or electric motor is attached to the shaft 4 and direct input/output to a digital computer is performed. It was possible to provide an inexpensive butterfly-shaped throttle valve device that can be controlled.

[Brief explanation of drawings]

Figure 1 is a longitudinal sectional view showing a conventional butterfly throttle valve device, Figure 2 is a sectional view of Figure 1, Figure 3 is an external view of a conventional butterfly throttle valve, and Figure 4 is a diagram showing the opening of the throttle valve. FIG. 5 is a longitudinal sectional view showing an embodiment of the butterfly-shaped throttle valve device of the present invention, and FIG. 6 is an explanatory view showing the drawing method of the fourth section 3. 1...Body 2...
・・・・・・・・・・・・・・・Bowleaf throttle valve 3・
・・・・・・・・・・・・・・・・・・Concave part 4・・・・・・
・・・・・・・・・・・・・・・Axis patent applicant Keihin Seiki Seisakusho Co., Ltd. Representative Watahiki Part 4 Figure 7 Figure 2 Figure 3 Figure 5

Claims (3)

[Claims] (1) Consists of a body 1 having an angular flow path and an angular butterfly-shaped throttle valve 2 rotatably supported by the body, and the opening area of the flow path can be adjusted by rotating the butterfly-shaped throttle valve. In a butterfly type throttle valve device that changes the amount of rotation of the butterfly type throttle valve, the four parts 3 are arranged on the body near the opening direction of the butterfly type throttle valve, and the opening area of the flow path is changed proportionally to the amount of rotation of the butterfly type throttle valve. Valve device. (2) Consists of a body 1 having an angular flow path, and an angular butterfly-shaped throttle valve 2 rotatably supported by the body.The flow path is opened by rotating the butterfly-shaped throttle valve. In a butterfly-shaped throttle valve device that changes the area, four parts 3 are arranged on the body near the opening direction of the butterfly-shaped throttle valve, and the opening area of the flow path is changed proportionally to the amount of rotation of the butterfly-shaped throttle valve. A butterfly-shaped throttle valve device in which a displacement gauge is attached to the shaft 4 of the throttle valve 2. (3) Consists of a body 1 having an angular flow path and an angular butterfly-shaped throttle valve 2 rotatably supported by the body, and the opening area of the flow path can be adjusted by rotating the butterfly-shaped throttle valve. In a butterfly-shaped throttle valve device that changes the butterfly-shaped throttle valve, four parts 3 are arranged on the body near the opening direction of the butterfly-shaped throttle valve, and the opening area of the flow path is changed proportionally to the amount of rotation of the butterfly-shaped throttle valve, and the butterfly-shaped throttle valve A butterfly-shaped throttle valve device in which an electric motor is attached to the shaft 4 of the valve 2.