JPS588929Y2 - Carburetor with starter - Google Patents

Description

[Detailed explanation of the invention] This invention is suitable for smooth operation (in cases where the starter is started immediately after starting in a cold region).
This is the configuration that will allow you to move on to this driving mode.

Conventionally, a carburetor with a starter (in this case, immediately after starting (
When the throttle is opened and the engine is started, the air-fuel mixture becomes diluted, making it difficult to continue rotating smoothly.

For this reason, it was customary to let the engine warm up for a while after startup before starting, but in the case of two-wheeled vehicles, this was an unfavorable condition from the viewpoint of agility, which is a characteristic of motorcycles.

The present invention (in view of these problems, the present invention was developed in such a way that the engine starts immediately after starting as much as possible).The present invention will be explained below with reference to figures showing embodiments thereof.

1 is the carburetor body, 2 is the throttle valve, 3 is the jet needle, 4 is the main nozzle, 5 is the main air passage, 6 is the starter plunger, 6A is the knob that pulls up the plunger,
T is a starter air passage, and the intake port is open to the intake passage f upstream of the throttle valve.

8 is a starting mixture chamber, and 8A is a starting mixture passage that communicates the mixture chamber with the intake passage downstream of the throttle valve.

Reference numeral 9 denotes a starting fuel passage, which is a main component of a conventionally known carburetor with starter.

Reference numeral 10 denotes a negative pressure operating device, which includes a pressure chamber 12 and an air chamber 13 separated by a diaphragm 11, which houses a spring 14 and a passage 151 which separates the starting mixture chamber 8. Communicate.

16 is a valve that fixes the diaphragm, and when the seat 17 (diaphragm) comes into close contact with the air chambers 1B and 13, it blocks the communication between the air chambers 1B and 13 and opens the passage 2.
Bleed air through 0 is cut off.

In the state shown in the figure, the air chambers 18 and 13 are in communication, that is, they are connected so that air is supplied through the passage 20.

19 is a passage that communicates the main air passage 5 and the air chamber 13, 20 is a passage that also communicates the main air passage 5 and the air chamber 18, and 21 and 22 are throttles.

The above configuration (to explain its function first, the figure shows the state before starting, the throttle valve is fully closed (the scooter plunger is fully open, and the main air passage 5) is the throttle valve 21 and 221. This allows a regulated amount of air to be supplied.

If the engine is started in this condition, strong negative intake pressure downstream of the throttle valve will be applied to the passage 8.
A to the mixture chamber 8, where air is drawn from the passage 7 and fuel from the passage 9, a mixture is formed in the chamber, and the mixture is supplied to the engine from the passage 8A.

In this case, since intake negative pressure is built up in the negative pressure actuation device 10 through the passage 15, the diaphragm 11 is pulled and the valve 16 is pulled.
The seat part 17 (this is in close contact with the seat part 17).

In this state, if you raise the throttle valve a little and move one mile, passage 15
(Although the negative intake pressure becomes weaker, the diaphragm is still attracted by adjusting the spring 14 of the diaphragm, so the passage 20 communicating with the main air passage I is blocked and the main air bleed air is passed through the throttle 21. Therefore, the mixture ejected from the main nozzle 4 forms a rich mixture, which, in combination with the rich mixture supplied from the starting mixture passage 8A, makes it possible to drive in cold climates. It can be continued smoothly.

When the starter plunger is pressed down and closed during steady running, the passage 15 is closed by the plunger side wall 1, so the diaphragm 11 is pushed by the spring 14 and moves to the right, opening the valve 16 and opening the main air passage 5I. In addition to the diaphragm 21, air is also supplied through the diaphragm 22.

Therefore, if the amount of air required to achieve a proper mixture ratio in steady running is the total amount of throttles 21 and 22, then in the case of immediate start-up (in this case, the air volume is supplied through the throttle 22). is closed, forming a rich mixture.

In the embodiment, two throttles 21 and 22 are provided, and one of them is turned ON and OFF. It may also be configured to completely shut off the device.

Further, it goes without saying that the starter plunger may be of a disc type.

As described above, the present invention makes it possible to supply a rich mixture from the main nozzle separately from the mixture supplied from the starting mixture passage when starting immediately after driving in a cold region. Since it is possible to independently set the main system, it has a great effect on improving the feeling when driving in cold regions.

[Brief explanation of the drawing]

The figure is a sectional view of essential parts showing an embodiment of the present invention 2... Throttle valve, 5... Main air passage, 6... Starter plunger, 10... Negative pressure actuation device, 16...
··valve.

Claims (1)

[Scope of utility model registration request] A carburetor 1 having a starter and a main air passage 5 is separated into a diaphragm 11 (thereby a pressure chamber 12 housing a spring 14 and an air chamber 13) and a valve 16.
is provided with a negative pressure actuating device 10 which is fixed to the diaphragm and which is fixed to the valve 16 to thereby adjust the amount of main air air, and connects the pressure chamber 12 of the device and the starting mixture passage to a passage 151. This is a carburetor with a starter device configured so that the passage 15 is opened and closed in response to the opening and closing of the starter.