JPH0142700Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flow control valve that is opened and closed by a diaphragm, and more particularly to a flow control valve that is suitable as a valve for controlling various air flow rates used in internal combustion engines.

Conventionally, various flow control valves operated by engine suction negative pressure have been used. It is preferable that such a flow valve has good controllability and can realize various special flow characteristics. Flow control valves having special flow characteristics have been proposed in Japanese Utility Model Publication No. 52-21328 and Japanese Patent Application Laid-open No. 52-44333.
Previously, in Japanese Utility Model Application No. 59-52537 (Japanese Utility Model Application No. 164183-1983) filed by the same applicant, a suitable flow rate control valve was proposed which utilizes swirling flow to achieve the above object.

In such a flow control valve, the inlet is generally connected to the upstream side of the carburetor, and the downstream thereof is connected to the downstream side of the carburetor, so that dust passing through the air filter or blown from the engine is Since the returned suspended carbon flows through such a flow control valve and is deposited inside the flow control valve, there is a possibility that the flow characteristics of the flow control valve may be impaired.

The present invention is a flow control valve that uses swirling flow as described above, and is designed to prevent unfavorable changes in flow characteristics due to floating carbon, dust, etc. adhering and accumulating on the valve body or valve seat. The purpose of the present invention is to provide a flow control valve.

According to the present invention, this purpose is achieved by a valve consisting of a valve seat member having a valve hole on the axis of a substantially cylindrical casing, and a valve body that is operated to open and close by a diaphragm to open and close the valve hole. In a flow rate control valve in which a first valve chamber having a fluid inlet and a second valve chamber having a fluid outlet are separated, the fluid inlet is aligned with respect to the axis in order to form a swirling flow of the fluid. The first valve chamber is connected to the first valve chamber in a substantially perpendicular direction, the fluid inlet is opened in a tangential direction of the casing, and the inner circumferential wall of the first valve chamber is uneven. This is achieved by providing a flow control valve with a Since the inner circumferential wall of the first valve chamber is uneven, foreign substances floating in the fluid settle from the fluid that stagnates along the wall surface and are deposited at the bottom of the first valve chamber and other appropriate places. Since floating carbon, dust, etc. are difficult to adhere to and accumulate on the valve body and valve seat, their flow characteristics will not be impaired even after long-term use.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view showing the entire flow control valve for air-fuel ratio control as an embodiment of the present invention.

A valve seat 5 is fitted into the center of the casing 1, which has a generally cylindrical shape with a closed bottom. Two valve chambers 16 and 17 are defined. As clearly shown in FIG. 2, the upper valve chamber 16 is integrally provided with a fluid inlet 3 that is perpendicular to the axis of the casing 1 and opens in the tangential direction of the casing. The side valve chamber 17 is also integrally provided with a fluid outlet 4 which is perpendicular to the axis of the casing 1 and opens in the tangential direction of the casing 1. Hole 1
5 and 15 are screw holes for screwing the casing.

The upper part of the casing 1 is closed by a cover plate 8, and the upper end of the casing 1 extending above the cover plate has an outwardly expanded diameter, and a diaphragm 9 is held between the upper ends. A metal cover 2 is attached by caulking so as to do so. The cavity defined between the diaphragm 9 and the cover plate 8 is the hole 1.
0 communicates with the atmosphere, and the empty space defined between the diaphragm 9 and the cover 2 is connected to the air intake inlet 11.
It is connected to the engine's intake port (not shown).

The upper end of a valve rod 7 is fitted into the center of the diaphragm 9, and the valve rod 7 is fixedly connected to the valve body 6 after slidingly passing through the cover plate 8.
A retainer 1 is installed between the cover 2 and the diaphragm 9.
A compression coil spring 13 is interposed via 2, and constantly urges the diaphragm 9 downward in FIG.

Therefore, unless negative intake pressure is introduced from the intake inlet 11, the valve body 7 is pressed against the valve seat 5 by the biasing force of the compression coil spring 13, and the casing 1
Two valve chambers 16, 17 defined inside the valve chamber are isolated from each other.

Further, in order to promote the formation of a swirling flow, the fluid outlet 4 may also be provided tangentially to the casing 1, as shown in this embodiment, and is further shown by imaginary lines in FIG. Like casing 1
It is preferable that a generally conical guide piece 14 is provided protruding from the bottom.

Further, the outer circumferential wall 18 of the valve chamber 16 is formed in an uneven shape, and furthermore, an annular groove 19 is defined in the outer circumference of the valve seat 5. Therefore, floating carbon, dust, etc. floating in the air inside the valve chamber 16 are removed from the uneven wall surface 1.
Since it stagnates at 8, it adheres to the wall surface 18 or is trapped in the annular groove 19 below it.

Thus, according to the present invention, the valve body 6 and the valve seat 5
Because it is difficult for floating carbon, dust, etc. to adhere to and accumulate on the
Its flow characteristics remain unchanged even after long-term use.

The shape of the above-mentioned uneven wall surface is not limited to a sawtooth shape as in the case of this embodiment, but may be any shape that can form a stagnation part of the air flow, such as a gear shape or any other shape. It may have an uneven shape.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a flow control valve according to the present invention in a closed state. FIG. 2 is a cross-sectional view taken along the - line in FIG. 1. DESCRIPTION OF SYMBOLS 1... Casing, 2... Cover, 3... Fluid inlet, 4... Fluid outlet, 5... Valve seat, 6... Valve body, 7... Valve stem, 8... Lid body, 9... Diaphragm , 10... hole, 11... negative pressure inlet, 12...
Retainer, 13... Compression coil spring, 14... Guide piece, 15... Screw hole, 16, 17... Valve chamber,
18... Wall surface, 19... Annular groove.

Claims (1)

[Claims for Utility Model Registration] A valve comprising a valve seat member having a valve hole on the axis of a substantially cylindrical casing and a valve body operated to open and close by a diaphragm to open and close the valve hole, having a fluid inlet. In a flow control valve formed by separating a first valve chamber and a second valve chamber having a fluid outlet, the fluid inlet is oriented substantially perpendicular to the axis to form a swirling flow of the fluid. is connected to the first valve chamber, the fluid inlet is opened in a tangential direction of the casing, and the inner circumferential wall of the first valve chamber is uneven. valve.