JPS6032028B2 - Carburetor automatic starting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic starting device for a carburetor, and more particularly, to a starting device that automatically opens and closes a carburetor starting valve depending on the condition of an engine at the time of starting.

Various types of automatic starting devices for carburetors of this kind have been developed, but none have been developed that can correctly adapt the opening of the carburetor starting valve to the engine temperature when starting the engine.

In the present invention, when starting an engine, the opening and closing operations of the carburetor starting valve are performed by a starting valve actuator operated by negative pressure in an engine suction pipe, and a negative pressure path is led from this suction pipe to the starting valve actuator. By placing a temperature in the middle of the engine, negative pressure is applied to the starting valve actuator in accordance with the engine temperature, and the carburetor starting valve is controlled to an appropriate opening degree in accordance with the engine temperature, and also in accordance with the engine temperature. The purpose of this is to ensure that all starter valves operate quickly and reliably. To explain the automatic starting device according to the present invention with reference to the drawings, Fig. 1 is a mechanical diagram showing the state of the starting device according to an embodiment of the present invention in a normal cold state (when the engine is stopped). The one attached to the plunger type starter device is shown.

Reference numeral 1 designates a plunger type starter unit, 2 a starter valve actuator according to the present invention, and 3 a valve device attached to the starter valve actuator.

The starter valve actuator 2 includes a first negative pressure chamber 23 between the negative pressure operating diaphragms 21 and 22, and a second negative pressure chamber 24 for operating the diaphragm 22, and presses the diaphragm 21 into the negative pressure chamber 23. A spring 25 is built into the negative pressure chamber 24, and a spring 26 for pressing the diaphragm 22 is built into the diaphragm 21. An operating rod 27 is attached to the diaphragm 21 to open and close the carburetor starting valve. A pressing rod 28 is attached. 29 is an atmospheric chamber.

The negative pressure chamber 23124 has a temperature-sensitive valve 30 that senses the engine temperature, for example, the temperature of the cylinder head, lubricating oil, exhaust pipe, etc., and connects or shuts off communication with the atmosphere, and a passageway 4104, respectively.
Connected by 2.

The temperature-sensitive valve 30 incorporates two inverted bimetals 32 and 33 that are press-fitted on both sides of a spring 31. The bimetal 32 faces the closed end of the lotus passage 41 from the pressure chamber 23, and when the temperature is low, it is pressed against the circle ring 34 of the closed part and closes the passage 41.
When the temperature of the engine reaches its final temperature, it is reversed and the 4-tatami lotus passageway is opened to the atmosphere. Also, the bimetal 33 is connected to the negative pressure chamber 24.
It faces the opening of the lotus passage 42 from the bottom, and when the temperature is low, it comes into pressure contact with the ○ ring 35 of the entrance and closes the communication passage 42, and when the engine temperature rises (at the beginning of the waist machine after the engine is completed). It is reversed and the lotus passage 42 is opened to the atmosphere. Reference numeral 36 denotes an atmospheric ventilation port of the temperature-sensitive valve 30.

Bypasses 43144 are provided in each of the above passages 48142, check valves 45'46 are placed in each of the bypasses, and the rain check valves are further connected to a temperature sensitive valve 50' connected to the engine intake.

In the figure, the lotus passages from the check valve 45046 are combined into one lotus passage 47, which is used to control engine suction pipe negative pressure.
It is connected to an overflow valve 50 that shuts off. In other words, check the above. The valves 45 and 46 are both opened when the lotus passage 47 becomes negative pressure, allowing the lotus passages 41 and 42 to communicate with the lotus passage 47. The temperature-sensitive valve 50 operates by sensing the engine temperature in the same way as the above-mentioned temperature-sensitive valve 30. At low temperatures, the inverted bimetal 51 opens the suction pipe passage 52, but when the engine is At this temperature, the bimetal 51 is inverted and pressed against the circle ring 53 at the closing portion of the lotus passage 52, thereby closing the lotus passage 52. 54 imitates the pressure of the bimetal 51.

A bracket 60 for holding the actuator 2 is also attached to the lower part of the actuating rod 27 attached to the diaphragm 21 of the starter valve actuator 2, and the upper part of the dogleg-shaped lever 61 is rotatably attached. Therefore, when the rod 27 is moved upward, the lever 61 is rotated counterclockwise, and when the rod 27 is moved downward, the lever 61 is rotated clockwise. Further, the upper part 61 has an elongated hole 62 in the lower part thereof, and the outermost hole 62 engages with a pin 64 provided on the tank moving shaft 63 that continuously moves the starting plunger 11 of the carburetor starting device 1. do. 65 is a lever connecting the starting plunger 11 and the sliding shaft 63, 12 is a carburetor intake cylinder, 13 is a starting air intake port, 14 is a starting fuel passage, and 15 is a starting mixture intake port. be.

Therefore, when the rod 27 of the starting valve actuator 2 is in the lowered position (the normal position when the engine is stopped as shown in FIG. 1), the sliding koji 63 is pushed to the left, and the plunger amount is The air-fuel mixture inlet 15 is closed (normal position). When the rod 27 rises, the sliding shaft 63 slides to the right, and the starting air-fuel mixture suction row 5 is opened. Since the structure is as described above, when the engine is started in the state shown in FIG. 451
46; Acts on the lotus passage turtle 10 turtle 2 and the negative pressure chambers 23 and 24 of the starter valve actuator 2, pulls up the diaphragm 22 to the highest position, and also moves the diaphragm 21 so that the top of its rod 27 is connected to the push rod 28 of the diaphragm 22. Pull it up until it touches the bottom (pull up the rod 27 all the way). Therefore, the starting plunger 11 of the carburetor starting device 1 is fully slid to the right to fully open the air-fuel mixture intake row 5. This state is shown in FIG. Then, when the engine is operated and the engine cools down, the bimetal 51 of the temperature-sensitive valve 50 is reversed to cut off the negative pressure in the suction pipe. However, negative pressure is maintained in the lotus passages 47, 41, and 42, and the negative pressure chambers 23 and 24 are also kept at the same negative pressure. Then, when the engine temperature rises a little further, the bimetal 3 of the temperature-sensitive valve 30
3 is reversed and conveys the lotus passage 42 to the atmosphere. Therefore, both the lotus passage 47 and the negative pressure chamber 24 are brought to atmospheric pressure, but since the check valve 45 is closed, the lotus passage 41 and the negative pressure chamber 23
Negative pressure is maintained. Therefore, the diaphragm 22 is pressed by the spring 26 of the negative pressure chamber 24, the rod 27 is lowered by that amount, and the starting plunger 11 partially closes the starting air-fuel mixture inlet T5. This state is shown in FIG. When the engine is further warmed up and the temperature-sensitive valve 30 reaches the engine completion temperature, the bimetal 32 is also reversed and the lotus passage 41 is returned to atmospheric pressure, so the negative pressure chamber 23 is also brought to atmospheric pressure, and the diaphragm 21 is fully filled. The starting plunger 11' is lowered to close the starting air-fuel mixture inlet 15.

That is, it will be in the position shown in FIG. As described above, according to the device according to the present invention, the starting valve automatically operates when starting in a cold state.
The starting valve is forced to the starting position, and the starting valve is returned to the normal position according to the degree of engine heating (the negative pressure chamber of the starting valve actuator 2 is increased, and the negative pressure chamber and the atmosphere are changed accordingly depending on the engine temperature). By increasing the number of temperature-sensitive valves that can be shut off and opened, the return stage of the starter valve can be increased and the return operation can be made small or medium), and once the engine has been fully stabilized, the starter valve will be forcibly returned to its normal position. It will be returned to. If the diaphragm of the negative pressure chamber of the starter valve actuator is made to have a large effective area,
The actuation force for actuating the starting valve is increased to eliminate the need for temperature-sensitive wax or the like even when the carburetor starting valve is of a plunger type. Also, the tank moving shaft 63 and the starting plunger 1 are slidably moved by the operating rod 27 of the starting valve actuator 2 mentioned above.
If a plurality of levers 65 connecting 1 are attached to the sliding shaft 63 in different directions, and each lever is connected to a plunger for starting a separate carburetor, a multiple carburetor can be obtained. Even in the case of a device, the above-mentioned starting valve actuator device can automatically operate the starting valves of a plurality of carburetors.

[Brief explanation of drawings]

Fig. 1 is a mechanical diagram showing the state of the starting device according to an embodiment of the present invention during normal cold operation (when the engine is stopped); Fig. 2 shows the state when a cold starting operation is performed; FIG. 3 shows the state of the starting device of the present invention at the time when the engine is started and the engine is stopped. 1... Starting device, 2... Starting valve actuator, 3... Valve device, 11... Starting valve (starting plunger), 21, 22... ...Diaphragm, 23...
...First negative pressure chamber, 24...Second negative pressure chamber, 25.2
6...1 pressure spring, 27...operating rod, 28...push rod, 30...atmosphere communication overflow valve, 32, 33...temperature sensing Valve, 50... Suction pipe Rentsu temperature sensing valve, 36... Atmospheric communication □, 41.
42...Lotus passage, 43.44...'Bypass, 4
6.46...Check. Valve, 47... Reach passage, 52... Suction pipe lotus passage. Figure 2 Figure 3 Figure 1

Claims (1)

[Claims] 1. A starter valve actuator having a first negative pressure chamber and a second negative pressure chamber each containing a negative pressure operating diaphragm pressed by a pressure spring, the first negative pressure chamber being opened at the engine warm-up completion temperature. The second negative pressure chamber communicates with the atmosphere through a temperature-sensitive valve, and the second negative pressure chamber communicates with the atmosphere through a temperature-sensing valve that opens at the initial warm-up temperature of the engine. Each communication passage is connected to the suction pipe via a temperature-sensitive valve that is opened when the engine is cold and closed when the engine is slightly warmed up to the initial warm-up temperature or lower, and the first negative pressure of the starting valve actuator is The diaphragm of the chamber is provided with an actuation rod that engages with the carburetor starting valve, and the diaphragm of the second negative pressure chamber engages with the diaphragm of the first negative pressure chamber when the diaphragm is pulled by the suction pipe negative pressure. A push rod is attached, so that both negative pressure chambers of the starting valve actuator become negative pressure in the suction pipe when the engine is cold started, and both diaphragms are pulled up fully, and the actuating rod of the first negative pressure chamber becomes the carburetor. The starting valve is located at the engine starting position, and the second negative pressure chamber becomes atmospheric pressure at the initial engine warm-up temperature, and its diaphragm is pressed to operate the carburetor starting valve to the side where the mixture is supplied to the engine. An automatic starting device for a carburetor, characterized in that the first negative pressure chamber also reaches atmospheric pressure at the engine warm-up completion temperature, and its diaphragm is fully pressed to return the carburetor starting valve to its normal position.