JPS591088Y2 - Vaporizer throttle valve opening/closing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle valve opening/closing device for a carburetor, which uses a return spring to close the throttle valve.

In general, the smaller the opening of the carburetor throttle valve, the greater the intake negative pressure from the engine.As a result, the frictional force of the sliding part of the throttle valve increases and its closing resistance increases. The return spring of the valve reduces its return force as the opening of the throttle valve decreases, so the closing of the throttle valve by the return spring tends to lack smoothness in the low opening range, especially for piston type throttles. This tendency is remarkable for valves.

Conventionally, the return spring is made strong so that the throttle valve can be reliably closed to the normal idle opening, but in this case, the closing force of the return spring is more than necessary in the high opening range. This causes the inconvenience that the valve opening operation becomes difficult.

In view of the above, it is an object of the present invention to provide a throttle valve opening/closing device that does not cause the above-mentioned disadvantages even when the return spring of the throttle valve is made strong.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. Reference numeral 1 denotes a carburetor main body, and a valve that slides together an intake body 2 that connects to the intake pipe of the engine, and a piston-type throttle valve 3 that opens and closes an intake passage 2a inside the body. It is made up of tube 4.

An operating shaft 5 is rotatably supported at the upper part of the valve cylinder 4 and connected to the throttle valve 3 via a link mechanism 6.

The end of the actuation shaft 5 protruding outside the valve cylinder 4 has a first and a second
Mount the actuating lever 7.8 adjacently.

In this case, the first operating lever 1 is rotatably loosely fitted to the operating shaft 5, and the second operating lever 8 is integrally connected to the operating shaft 5 by a push screw 9.

The first operating lever 7 is shaped like a pulley with a wire guide groove on its outer periphery, and is linked to a drive pulley 12 of a throttle valve operating mechanism 11 such as an accelerator grip via a pair of wires 10 and 10'.

On the other hand, the second operating lever 8 and the locking portion 13 of the carburetor main body 1
A coiled return spring 14 is tensioned between the coiled return spring 14 and its tensile force to bias the second operating lever 8 in the direction of closing the throttle valve 3.

In this case, a strong spring is used as the return spring 14 so that the throttle valve 3 can be reliably closed to the normal idle opening degree without being hindered by the engine's intake negative pressure.

Furthermore, a first piston 17 with a small diameter is connected to the first actuating lever 7 via a connecting rod 15, and a second piston 1B with a large diameter is connected to the second actuating lever 8 through a connecting rod 16. .1B is the first one fixed to the carburetor body 1.
and the second cylinders 19 and 20, respectively.

Both cylinders 19.2G communicate with each other via a passage 21, and a low viscosity liquid 22 is sealed inside them.

Next, to explain the operation of this embodiment, first, the drive pulley 1
2 clockwise in the figure to pull the wire 10, and the first operating lever 7 is also rotated clockwise, the first piston 17 is pushed into the first cylinder 19 via the connecting rod 15. As the liquid 22 in the first cylinder 19 is pumped into the second cylinder 20, the second piston 18 is pushed outward.

At this time, the pressing force of the first piston 17 can be amplified and taken out from the second piston 1B due to the difference in the pressure receiving areas in the cylinders 19, 20 of both pistons 17, 18, so that the large pressing force of the second piston 18 is Continuous rod 16 due to pressure
Through the second operating lever 8, the operating shaft 5, and the link mechanism 6, the throttle valve 3 can be opened easily against the strong spring force of the return spring 14.

Next, by releasing the rotational force applied to the drive pulley 12 or rotating it counterclockwise, the throttle valve 3 can be reliably closed by the strong spring force of the return spring 14, and the drive pulley 12 side There is almost no load on , and each piston 17.1
Since the sliding resistance of 8 is extremely small, both pistons 17.1
8 can be smoothly returned to its original position.

As described above, according to the present invention, the rotational force of the first operating lever 7 connected to the throttle valve operating mechanism 11 is transferred from the small diameter first piston 17 to the large diameter second piston 8 connected to the throttle valve 3. Since the hydraulic pressure can be amplified and transmitted by the hydraulic pressure transmission action to the piston 18, the opening operation of the throttle valve 3 can be easily performed against the strong spring force of the return spring 14. In other words, the opening operation can be performed easily. Return spring 14 without any concern about force increase
By setting the spring force as strong as desired, the throttle valve 3 can always be reliably closed without being hindered by the engine's intake negative pressure.

Moreover, since the force is transmitted between the pistons 17 and 18 via the liquid 22, there are fewer mechanical friction parts and the throttle valve 3 can be opened and closed more easily.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional side view of the main part of a vaporizer equipped with the device of the present invention;
FIG. 2 is a sectional view taken along the line II--II in FIG. 1. 1... Carburetor main body, 3... Throttle valve, 5... Operating shaft,
7...First operating lever, 8...Second operating lever, 1
1... Throttle valve operation mechanism, 14... Return spring, 17...
・First piston, 1B...Second screw 1~n, 19...
・Second cylinder, 20...Second cylinder, 22...
liquid.

Claims (1)

[Scope of utility model registration request] In the carburetor in which the throttle valve 3 is closed by the strong spring force of the return spring 14, the first operating lever 7 connected to the throttle valve operating mechanism 11 and the second operating lever 8 connected to the throttle valve 3 are connected to the carburetor. A first piston 17 with a small diameter and a second piston 18 with a large diameter, each rotatably supported on the main body 1 and connected to the first actuating lever 7, communicate with each other and are internally connected to each other. A throttle valve opening/closing device for a vaporizer, which is formed by sliding on first and second cylinders 19 and 20, each containing a liquid 22.