JPS6218744B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an auto-choke mechanism. Conventional mechanisms of this type detect the engine condition using heat, and control the air-fuel ratio required by the engine by opening and closing a chi-yoke valve. It was made into a spiral shape, and the heat, which indicates the engine's condition, was converted into power to open and close the chiyoke valve. A so-called thermowax system was also created in which wax was used instead of a bimetal and a piston-sealed pellet was used to open and close the choke valve, but in this thermowax type autochike, the movement of the piston in the wax was small relative to the temperature. In order to magnify it, some use a gear mechanism to change the force of the closing spring of the choke valve. but,
This is mechanically complex and requires many parts, which is disadvantageous in terms of accuracy, production, and cost. Therefore, as shown in the figure, in order to change the opening/closing force of the choke valve according to the engine condition, the inventor sensed the engine condition by heat and operated the thermowax piston, and applied the operating force via the first lever. a second end of the torsion spring and engaged with the other end of the torsion spring;
The carburetor is taken out via a lever, and the second lever is engaged with a third lever provided on the mounting shaft of the choke valve so that the lever can be operated in any swinging direction of the second lever. An automatic yoke mechanism was proposed. However, in this case, if the movement of the piston of the thermowax is directly connected to the lever that opens and closes the valve, there is a risk that unreasonable action will be exerted on the parts, leading to deformation or damage to the parts.

In view of the above, this invention has been improved to prevent parts from deforming or breaking. In other words, the thermowax, which operates by sensing the engine temperature related to the engine's required air-fuel ratio or a temperature close to it, and the same shaft a wax-side lever that engages with the piston of the thermowax provided on the thermowax and is always biased in the engagement direction; a wax-side lever that controls opening and closing of the chi-yoke valve; and a wax-side lever that once engages with the wax-side lever and the other end has a first torsion spring 4 that engages with the lever on the yoke side, and the shaft 10 is also provided with an idle lever 27 having two hooks 27' and 27'' formed protrudingly, one hook 27 ' to the wax side lever 3 and the other hook 27'' to the York side lever 5 so that the engaging directions are opposite to each other, and one end engages the hook 27', the other A second torsion spring 28 is provided, the end of which engages with the front lever, and the second torsion spring 28, like the first torsion spring 4, acts to be rolled up by the advance of the piston of the thermowax. 1st
The torsion spring 4 is reinforced.

Next, embodiments of the invention shown in the drawings will be described. 4 is a torsion spring with a hook 4' at one end.
is fixed to the adjustment screw 25 and rotated left and right around the shaft 10. Reference numeral 3 denotes a wax side lever which is engaged with the tip of the piston 2 of the thermowax 1, transmits the movement of the piston 2 to the torsion spring 4 via the lever, and whose lower end forms a fast idle cam 3'. As the engine warms up, the thermowax expands and its piston 2 protrudes to the left, and the wax-side lever 3 rotates clockwise around the shaft 10. At a set temperature, the torsion spring 4 applies force in the opening direction of the chiyoke valve. However, the valve may not open due to the deflection of the spring, so the lever 3 on the wax side
A hook 3'' is formed protrudingly on the shaft 10, and the hook 3'' is configured to contact the hook 27' of the idle lever 27 provided on the shaft 10.The wax-side lever 3 comes into contact with the hook 27' of the idle lever 27 at a certain temperature. In order to adjust it, you can bend it with an adjustment tool, but this requires skill, so as shown in the figure, insert the adjustment screw 26 into either the hook 3'' of the wax side lever 3 or the hook 27' of the idle lever 27. It is best to install it and improve workability by adjusting this adjustment screw. The hook 27'' of the idle lever 27 and the hook 5'' of the yoke side lever 5 are constantly pressed together by the elastic force of a torsion spring 28 provided on the shaft 10, and are integrally constructed. Torsion spring 2
The return force 8 is set to be stronger than the rotational frictional resistance between the lever 5 on the side of the yoke and the shaft 10. In the figure, 5' is the scissor-shaped part of the lever 5, 6 is the collar, 7 is the lever fixed to the yoke shaft, 8 is the pin, 9 is the adjustment screw, 11 is the yoke shaft, 13 is the unloader rod, 14 is the unloader lever, 15 is the return spring of the wax side lever 3, 16 is the throttle shaft, 17 is the throttle valve, 18 is the fast idle lever, 8' is the roller, 19 is the yoke breaker diaphragm case, 20 is the unloader lever, 21 is the yoke Breaker diaphragm rod, 22 is the tooth yoke lever hook for the yoke breaker, 23 is the yoke body, 24 is the yoke body mounting screw, and 25 is the adjustment screw.

As described above, when the temperature of the thermowax 1 decreases, the piston 2 retreats to the right, the wax-side lever 3 rotates counterclockwise around the shaft 10, and the adjustment screw 26 moves toward the hook 2.
It gradually becomes possible from 7'. Conversely, as the temperature rises, the screw 26 and the hook 27' gradually approach each other, and when the temperature exceeds a certain level, they come into contact and push the hook 27' until the yoke valve 12 is fully opened. If the temperature rises further, the other hook 27'' will become more spring 2 than hook 5''.
The hook 5 moves away against the force of 8, and the hook 5 stops at that position.

As described above, in this invention, the idle lever 27 is provided on the shaft 10 and connected to the front lever 5 via the torsion spring 28, and after the front valve is fully opened, the rotational force of the idle lever 27 is transferred to the torsion spring 28. By only being energized, it is possible to apply the necessary force in the direction of opening the check valve without applying unreasonable force to the check lever 5, and to ensure that the check valve starts to open at the predetermined thermowax temperature and reaches full opening. . In addition, since the movement of the wax-side lever 3 is transmitted from the idle lever 27 to the yoke-side lever 5 via the torsion spring 28, the force is transmitted softly and the yoke-side valve can be opened without strain, thereby deforming the parts. It has the advantage of not being damaged or damaged.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a top view, FIG. 2 is a front view, and FIG. 3 is a sectional view taken along line AA in FIG. 1. 1...Thermowax, 2...Piston, 3...
...Wax side lever, 4...First torsion spring,
4'...Hook, 5...Yoke side lever, 5''...
...Hook, 10...Shaft, 12...Chewing valve, 26...Adjusting screw, 27...Idle lever, 27', 27''...Hook, 28...Second torsion spring.

Claims (1)

[Claims] 1 A thermowax that operates by sensing the engine temperature related to the engine's required air-fuel ratio or a temperature close to it, and a wax that engages with a piston of the thermowax provided on the same shaft 10 and is always biased in the engagement direction. In addition to having a side lever 3, a check side lever 5 for controlling opening and closing of the check valve, and a first torsion spring 4 having one end engaged with the wax side lever and the other end engaging with the check side lever, The shaft 10 has two hooks 2.
An idle lever 27 having protruding portions 7' and 27'' is provided, one hook 27' being engaged with the wax side lever 3, and the other hook 27'' being engaged with the York side lever 5 in opposite directions. a hook 28' that is in engagement relationship and that engages one hook 27' of the idle lever at one end;
A second torsion spring 28 is provided which has a hook 28'' at the other end that engages with the front lever 5, and the second torsion spring 28, like the first torsion spring 4, The first torsion spring 4
The autochoke mechanism of the carburetor is designed to reinforce the