JPS609424Y2 - Vacuum advance device for internal combustion engine ignition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum advance device for engine ignition of internal combustion engines, primarily automobiles.

In this type of device, the inside of the housing is divided by a diaphragm into an atmospheric chamber and a negative pressure chamber connected to the negative pressure outlet of the engine's suction system, and an ignition advance operating rod that penetrates the side wall of the atmospheric chamber is connected to the diaphragm. It is known that the diaphragm is connected to the diaphragm and a spring is disposed in the negative pressure chamber to determine the advance angle rise characteristic due to the negative pressure operation of the diaphragm.

In the above-mentioned device, the present invention aims to reduce the weight by molding the housing from synthetic resin, and the side wall of the housing is attached to a pair of stoppers that are attached to the operating rod and regulate the operating stroke to a predetermined amount. and both stoppers are molded from synthetic resin, thereby simplifying the stopper structure and buffering the contact impact between the two stoppers and their contact parts. The purpose is to

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a hollow cylindrical synthetic resin housing, the interior of which is divided by a diaphragm 2 into a negative pressure chamber A and an atmospheric chamber B.

The negative pressure chamber A is connected to a negative pressure detection hole 5 via a negative pressure introduction pipe 6 as a negative pressure chamber outlet opening into the venturi portion 4 of the internal combustion engine carburetor 3 .

7 is a throttle valve provided downstream of the venturi section 4.

A dish-shaped mounting plate 9 with a spring receiver 8 is placed on the negative pressure chamber A side of the center of the diaphragm 2, and a similar dish-shaped mounting plate 10 is placed on the atmospheric chamber B side, and the center of these 9° 10 Atmospheric chamber B
One end of an ignition advance operating rod 11 passing through the side wall 1a is fixed.

The other end of the operating rod 11 is connected to and operates an ignition interrupter (not shown).

The operating rod 11 is provided with a pair of annular stoppers 12 made of Hewei resin that alternately abut the inner and outer surfaces of the side wall 1a. , 122 are fitted with the spacer 13 in between, and the stoppers 12 . ．． 12□
regulates the operating stroke of the operating rod 11 to a predetermined amount.

Both stoppers 12, . An annular stepped portion 15 opposite at 12°
□, 152 are formed, respectively.

A diaphragm 2 is disposed between the inner wall of the negative pressure chamber A and the spring receiving portion 8.
A spring 16 is provided that determines the advance angle rise characteristic due to negative pressure operation.

Next, this embodiment will be explained.

When the engine is idling, the negative pressure in the venturi section 4 of the carburetor 3 is low, and therefore the negative pressure in the negative pressure chamber A is also low, so the diaphragm 2 is pushed into the atmospheric chamber B by the elastic force of the spring 16. The stopper 12□ is connected to the annular stepped portion 15.
1, the operating rod 11 occupies the right movement limit position, and thereby the interrupter is maintained in a state where the ignition advance angle is zero.

The throttle valve 7 is opened to increase the output of the engine, and as the intake air amount of the engine increases, the negative pressure in the venturi section 4 increases, which acts in the negative pressure chamber A through the negative pressure introduction pipe 6. When the suction force acting on the negative pressure diaphragm 2 overcomes the set load of the spring 16, the diaphragm 2 is displaced to the left and the operating rod 11 is moved to the left.

Therefore, the ignition interrupter connected to the operating rod 11 is operated to advance the ignition timing, and when the outer stopper 12° comes into contact with the annular stepped portion 15□, the operating rod 11 moves to the left movement limit position. , which holds the interrupter at its maximum advance angle.

Thus, during engine operation, the operating rod 11 reciprocates as the throttle valve 7 opens and closes, and the stopper 12. ．． 12□ to the annular stepped portion 15. of the housing 1. ．． Alternately contact each other at 15 degrees,
The contact impact is applied to the synthetic resin housing 1 and the stopper 12. ．． Absorbed by 12□.

As described above, according to the present invention, since the housing 1 is made of synthetic resin and has a bottom shape, its weight can be reduced, and the side wall 1a of the housing 1 can be attached to the operating rod 11.
A pair of stoppers 12 for regulating the operating flow to a predetermined amount. ．． 12° contact portion and both stoppers 12
．． , 12° are made from synthetic resin, which simplifies the stopper structure and reduces the contact impact of both stoppers 12□, 12□ and their abutting parts with the elasticity of the synthetic resin, thereby eliminating unpleasant noises. In addition, the housing 1 and both stoppers 12. , 12° can be manufactured very easily.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of an embodiment of the present invention. A...Negative pressure chamber, B...Atmospheric chamber, 1...
...Housing, 1a...Side wall, 2...
...Diaphragm, 5...Negative pressure detection hole as a negative pressure outlet, 11...Ignition advance operating rod, 12
1,122...stopper, 16...spring.

Claims (1)

[Scope of utility model registration request] The interior of the housing 1 is divided by a diaphragm 2 into an atmospheric chamber B and a negative pressure chamber A connected to a negative pressure outlet 5 of the engine suction system, and an ignition advance operating rod 1 passes through a side wall 1a of the atmospheric chamber B.
1 is connected to the diaphragm 2, and a spring 16 is disposed in the negative pressure chamber A to determine the advance rise characteristic due to negative pressure operation of the diaphragm 2, wherein the housing 1 is molded from synthetic resin, A pair of synthetic resin stoppers 12 □, 12 are provided on the ignition advance operating rod 11 to alternately contact the inner and outer surfaces of the side wall 1a of the atmospheric chamber B to restrict the operating stroke of the ignition advance operating lever 11 to a predetermined amount. Vacuum type for internal combustion engine ignition with ゜