JPS5846276A - Double reed valve - Google Patents

Abstract

PURPOSE:To obtain required flow-rate controlling characteristics of a valve, by making the sectional areas of valve sheets and the setting angles of stopper plates different from each other, and thereby achieving stepwise operation of the valve sheets. CONSTITUTION:A valve body 7 is formed with a inclined valve seat 7a, on which two valve sheets 8, 9 having different sectional areas are seated. Further, a stopper plate 10 for restricting the deflection of the valve sheet 8 is fixed above the sheet 8 such that its setting angle to the surface of the valve seat 7a is greater than that of a stopper plate 11 for the valve sheet 9. When the negative pressure produced in operating an engine or the like is low, the sheet 9 alone is opened to an angle corresponding to the load since the spring constant of the sheet 9 having a smaller sectional area is small than that of the sheet 8. Along with increasing of the load, the sheet 8 also begins to open, and at a certain load, the sheet 9 comes into contact with the stopper plate 11. With further increasing of the load, the sheet 8 also comes into contact with its stopper plate 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a biplane reed pulp that can achieve the required flow rate control by varying the cross-sectional area of each valve seat and the installation angle of each stopper plate.
Sur.

Reed pulp, which is bent by the pressure difference between the upstream and downstream sides and controls the flow rate, is used in various fields as a type of check valve.

For example, in the case of reed pulp installed in the mixture passage of an internal combustion engine, in order to obtain higher suction efficiency from the low speed range to the high speed range of the engine, multiple valve seats are used, that is, a so-called biplane type, and each Lower the spring constant of the valve seat
It facilitates white deformation and facilitates flow rate control.
.

However, in the above-mentioned biplane reed pulp, since the dimensions and shape of each loop 44 are the same, the spring constant of each valve seat is the same, and therefore the spring constant of each valve seat should be set mainly for high speed range. For example, if the spring constant is set high, the ability of each valve seat to follow the engine negative pressure will deteriorate in the low speed range, and the suction efficiency in the low speed range will decrease; conversely, the spring constant will be set low mainly in the low speed range. If this occurs, each valve seat will operate abnormally, reducing the suction efficiency in the high speed range, and in view of this problem in the entire engine speed range, the present invention has been developed to effectively solve this problem.
The purpose of this is to realize stepwise operation of each valve seat by making the cross-sectional area of each valve seat and the setting angle of each stopper plate different, thereby controlling the required flow rate. To provide biplane reed valves.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 is a partially cutaway side view of a vehicle internal combustion engine, Fig. 2 is a plan view of a reed valve according to the present invention, and Fig. 3 is Fig. 2-3.
The 3-line sectional view and FIG. 4 are graphs showing the flow rate control characteristics of the reed valve.

In FIG. 1, 1 is an engine, an intake pipe 2 is connected to a combustion chamber (not shown) formed inside the engine, and a carburetor for forming an air-fuel mixture is provided at the end of the intake pipe 2. 3 is connected to the carburetor 3, and an air cleaner device (not shown) is further connected to the carburetor 3.

A biplane type (two-leaf type in the illustrated example) reed valve 4 shown in detail in FIGS. 2 and 3 is located midway through the air-fuel mixture passage of the intake pipe 2.
is interposed. In addition, 5 in Figure 1 is a transmission case,
A power transmission device (not shown) for transmitting the power generated by the engine 1 to the wheels 6 is housed inside this.

The reed valve 4 is constructed as shown in FIGS. 2 and 3. That is, 7 in the figure is a valve body with a thousand-sided substantially rectangular shape.
An inclined valve seat 7a is formed on the valve body 7, and two valve seats 8 and 9 having different cross-sectional areas are seated on the valve seat 7a. These valve seats 8, 9 are integrally formed by punching an elastic metal plate, and each seat 8, 9 has a length t.
are equal, while for these widths t is one sheet 8
The width b' of the other sheet 19 is set larger than that b' of the other sheet 19. (bib') And on the upper surface side of the sheets 8 and 9 are respective seams)8.
9) Stopper play for regulating bending deformation heat) 10.
11 are provided. These Stotubahre ) 1
0. 11 is formed by punching or bending a highly rigid metal plate in one piece, and the set angle of these, that is, the angle formed with respect to the surface of the valve seat 7a, is higher for the plate 10 than for the other plate 11.
is set larger than .

Thus, the valve seats 8, 9 and the stopper plate 1
0 and 11 are fastened together to the valve body 7 with screws 12 and 12 with their one ends overlapped to form a seven-leaf type reed valve as shown in the figure.

Next, the function of the present reed valve 4 will be described.

During operation of the engine 1, the air-fuel mixture formed in the carburetor 3 passes through the air-fuel mixture passage of the intake pipe 2 and the reed valve 4 due to the negative pressure generated by the lowering of the piston (not shown) of the engine 1. It is sucked into engine 1.

In the low rotational speed range of the engine 1, the negative pressure generated by the engine 10 is small, so the suction force of the valve seat 8.9 is also small. As mentioned above, the valve seats 8 and 9 have different widths, and since one seat 8 is wider, it has a higher spring constant and is difficult to bend. Conversely, the other sheet 9 has a lower spring constant and is therefore more easily deformed, and initially only the sheet 9 opens with an opening degree that corresponds to the generated negative pressure. In this case, sheet 9
The response to changes in negative pressure generated is extremely good, and the flow control characteristics of this reed valve shown by solid line A and broken line B in Figure 4
As is clear from the comparison with the characteristics shown in , it is possible to increase the amount of intake air in the low engine speed range, and the intake efficiency can be increased accordingly.

FIG. 4 is a graph in which the horizontal axis is the engine speed and the vertical axis is the suction amount.

Next, as the engine speed gradually increases, the other valve seat 8 also begins to open gradually, and the suction amount gradually increases.

At the engine rotational speed, one seat 9 comes into close contact with the lower surface of the corresponding stopper plate 11 and cannot be opened any further. From then on, as the engine rotational speed increases, only the seat 8 changes its opening degree. When this 8 comes into close contact with the stopper plate 10 and both seats 8 and 9 are fully open, the maximum suction amount is obtained and the engine reaches its maximum rotational speed.

Thus, the valve seats 8, 9 over the entire speed range of the engine
As is made to open and close in stages, as is clear from FIG. 4, the amount of suction can be increased over the entire speed range, and therefore the suction efficiency can be increased over the entire speed range.

Also, the cross-sectional area of each valve seat 8, 9, stopper plate) 1
By mutually changing the setting angle of 0.11, the desired flow rate control characteristics can be easily obtained.

In the embodiment described above, the area of the valve seats is made different by making the width of each valve seat different, but instead of this, the length may be changed, and this also allows the spring tension between each valve seat to be different. Different constants can be used to effect stepwise actuation of the valve. Furthermore, although this embodiment has specifically explained a seven-leaf type reed valve, a biplane type reed valve having three or more valve seats can also be explained in the same manner.

As is clear from the above explanation, according to the present invention, since the cross-sectional area of each valve seat and the setting angle of each stopper plate are made different from each other, it is possible to realize the stepwise operation of each valve seat, thereby realizing the required operation. Flow control characteristics can be obtained.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a partially cutaway side view of a vehicle internal combustion engine, Fig. 2 is a plan view of a reed valve, and Fig. 3 is a sectional view taken along line 3-3 in Fig. 2. 1 and 4 are graphs showing flow 1 control characteristics of the reed valve. In addition, in the drawing, 2 is an intake pipe, 4 is a reed valve, 7 is a valve body, 7
a is a valve seat, 8 and 9 are valve seats, and 10° and 11 are stopper plates. Patent applicant Honda Motor Co., Ltd.

Claims (1)

[Claims] In a biplane reed pulp comprising a plurality of valve seats and a plurality of stopper plates that regulate the opening degree of the valve seats, the cross-sectional area of each of the valve seats and the angle (setting A biplane type valve 0 that is characterized by having mutually different angles.