JPS624665Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a starting device including a plunger for starting a carburetor. Various automatic starting devices for carburetors have been invented and devised, but in order to obtain good starting performance even in extremely cold weather, it is necessary to use a starting plunger-type starting device, in which the opening operation of the starting plunger at the time of starting can be manually operated. It is the best thing to do. The purpose of the present invention is to provide a starting device equipped with a starting plunger, in which the plunger is operated manually during starting, and after starting is completed, the plunger is automatically returned to its proper position according to the rise in temperature using a temperature-sensitive actuating device. let Another object of the present invention is to provide a starting device for a carburetor in which, in the unlikely event that the starting plunger becomes inoperable due to a failure of the temperature-sensitive actuating device, the plunger can be manually returned.

The starting device according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an embodiment of the carburetor starting device according to the present invention, showing a starting plunger section in cross section. FIG. 2 is a side view taken in the direction of arrow A in FIG. 1. The starting plunger chamber 1 is connected to a starting air passage 2 (shown by dotted lines) which leads from an air cleaner (not shown) (Figure 2 and 3 is the starting air intake hole from the air cleaner), and an intake pipe (shown by dotted lines). The starting mixture air passages 5, 5' communicate with the downstream side of the throttle valve 4 (as shown). Reference numeral 6 denotes a starting fuel passage leading from the carburetor fuel chamber 7. In the figure, the starting plunger valve 8 is pressed by its pressure spring 9, and the starting air passage 3.
A state in which the fuel passage 6 and mixture supply passages 5 and 5' are closed (normal state) is shown. A knob 11 for manual operation is provided at the tip of the plunger rod 10 of the plunger valve 8. Also, there is a bracket 12 in the middle part.
A plunger positioning step 15 is fixed, which is supported by a pivot shaft 13 implanted in the plunger and engages with an engagement lever 14 that is swung by a temperature-sensitive actuator 30, which will be described later. The positioning step portion 15 forms a tapered second step portion 17 with a first step portion 16, and a base portion 18 of the positioning step portion 15 slides with a semicircular engagement piece 19 attached to the upper surface of the intermediate portion of the engagement lever 14. Engagement pin 20 that engages freely
has been established. The engagement lever 14 has its pivot 1
The torsion spring 21 wound around the plunger positioning step 15 at the tip of the engagement lever 14
root part 18 (i.e. plunger rod 10)
is biased so as to press it upward. That is, the engagement lever 14 is biased clockwise in FIG.

The temperature-sensitive actuator 30 is attached to the bracket 22, has a built-in temperature-sensitive wax 31 as shown in FIG. 2, and is equipped with a ceramic heater 32 at the bottom thereof, which is energized when the engine is turned on. It is heated by this. 33, 33' are connected to a battery (not shown) through a main switch (not shown) to connect the ceramic
This is the lead wire connected to the heater. The operating head 34, which is slid up and down by the expansion and contraction of the temperature-sensitive wax 31, comes into contact with the adjusting screw 23 attached to one side of the engagement lever 14.

With this structure, when the plunger rod knob 11 is pulled fully (to the right in FIG. 1) when starting the engine, the engagement lever 14 is moved by the torsion spring 2.
1, the plunger positioning step 15 is pressed by the second step 17 (tapered portion) and the first step 16 and swings, and when the engagement lever 14 engages with the plunger rod 10, In other words, the plunger valve 8 is fully opened at the position where the side surface of the engagement lever 14 contacts the side surface of the first step portion 16. This state is shown in FIG. When the engine is started, the ceramic heater 32 of the temperature-sensitive actuator 30 is energized, the temperature-sensitive wax 31 is heated, and the engagement lever 14 is rotated counterclockwise (FIG. 2). After the engine has completely exploded, the engagement lever 14 descends to the first step portion 16 of the engagement step portion, and the engagement lever 14 comes to engage with the second step portion 17. That is, the side surface of the engagement lever 14 comes into contact with the side surface of the second step 17 of the plunger positioning step, and as shown in FIG. 4, the plunger valve 8 is returned to the half-open position, and the starting mixture supply path 5' is opened. Closed. As the temperature-sensitive wax is further heated, the engagement lever 14 is further swung counterclockwise, and when the engine is completely warmed up, the engagement lever 14 is also disengaged from the second step 17 and the plunger is moved. Valve 8 is fully closed (FIG. 1) (the ceramic heater is selected in capacity to match the expansion of the temperature-sensitive wax as described above).

The above describes an automatic adjustment mechanism for the supply air-fuel mixture in which the engaging lever 14 automatically returns the starting plunger valve 8 according to the engine temperature using a temperature-sensitive actuator after the engine is started. If there is a malfunction in the temperature actuator (heater malfunction or temperature-sensitive wax malfunction), the engagement lever malfunctions, that is, the plunger valve returns malfunctions, or for any other reason, cancel the starting system. If this happens (for example, due to driver error), manually turn the knob 11 of the plunger rod 10 to the second position.
When rotated clockwise in the figure, the engagement pin 20 provided at the root portion 18 of the plunger positioning step 15 presses the engagement piece 19 of the engagement lever 14.
The engagement lever 14 is rotated counterclockwise to disengage the engagement lever 14 from the plunger rod 10 and operate the plunger valve in the return direction. Since the engaging piece 19 attached to the engaging lever 14 has a semicircular shape, the engaging pin 20 is slidably engaged internally in the recessed portion of the engaging piece 19, so that the plunger・Rotsudo 1
Not only can the plunger valve be returned by the manual operation of 0, but also the plunger valve can be partially opened by the above-mentioned reverse operation (turning the knob 11 counterclockwise). Furthermore, since the heater 32 of the temperature-sensitive actuator is a ceramic heater, together with the use of wax as the temperature-sensitive actuator, the temperature-sensitive actuator can be made compact and its operating accuracy can be made highly and reliable. Further, although the above embodiment has shown a two-stage operation of the starting plunger valve, it is also possible to use a similar means to provide a fine adjustment type with a larger number of stages.

As described above, according to the starting device according to the present invention,
When starting the engine, an appropriate start is performed manually in any cold region or extremely cold weather, and after the engine is started, the supplied air-fuel mixture is automatically adjusted to an appropriate mixing ratio according to the temperature. Furthermore, even in the unlikely event that the temperature-sensitive operating device fails, it is possible to immediately switch to manual operation and perform the same operations and functions.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the starting device according to the present invention, showing a section of the starting plunger portion. FIG. 2 is a side view taken in the direction of arrow A in FIG. 1. Figure 3 is a plan sectional view similar to Figure 1 showing the state in which the starting plunger valve is fully open, and Figure 4 shows that the starting plunger valve is moved to the warmed-up position (half-open position) by temperature-sensing operation after the engine has completely exploded. ) is a sectional view similar to FIG. 3, showing a state in which the DESCRIPTION OF SYMBOLS 1... Plunger chamber, 8... Plunger valve, 10... Plunger rod, 13... Engagement lever pivot, 14... Rocking engagement lever, 15...
Plunger positioning step portion, 19...Engagement piece, 2
0... Engagement pin, 30... Temperature-sensitive actuator, 31...
Temperature-sensitive wax, 32...Ceramic heater.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a starting device for a carburetor that supplies starting air-fuel mixture by a plunger valve, the plunger rod for sliding opening/closing by manual operation of the plunger valve has a plunger positioning step and one end. A swinging engagement lever is provided, the other end of which is pressed by a temperature-sensitive actuator to engage a step on the plunger rod, and a pivot shaft of the engagement lever is provided on the positioning step of the plunger rod. 1. A starting device for a carburetor, characterized in that an engaging pin protruding in a direction and an engaging piece slidably engaged with the engaging lever in the operating direction of the engaging pin and the plunger rod are provided. (2) The starting device for a vaporizer according to claim 1, wherein the temperature-sensitive actuator has a built-in temperature-sensitive wax heated by a ceramic heater.