JPS6218752B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition timing control device used particularly in internal combustion engines for automobiles.

In general, adjusting the ignition timing of an internal combustion engine later (retard) or earlier (advance) as appropriate depending on engine operating conditions and output changes, etc. reduces harmful unburned components in the exhaust gas. However, the specific control patterns for the retard and advance angles should be set individually depending on the type and characteristics of the engine. Therefore, many ignition timing control devices having various control patterns of retard and advance have been proposed.

The present invention makes it easy to adjust the set load of the spring that determines the rising characteristics of the retard angle and advance angle in such a device, and also improves the sealing performance of the operating pressure chamber of the housing to ensure accurate operation at all times. , an object of the present invention is to provide the ignition timing control device.

In order to achieve this purpose, the present invention
The interior of the housing is divided into an atmospheric chamber that is constantly communicated with the atmosphere by a diaphragm, and an operating pressure chamber in which the introduced air pressure can be switched to positive pressure or negative pressure, and an operating rod that passes through a through hole provided in the side wall of the atmospheric chamber. A first adjusting member connected to the diaphragm and having both ends facing the inside and outside of the through hole and a second adjusting member located outside the through hole are screwed together so as to be adjustable forward and backward, and the first adjusting member is connected to the diaphragm and has both ends facing inside and outside the through hole, and A spacer holding piece protruding from the intermediate portion of the first adjusting member and a pair of spring receiving plates facing each other across the side wall are slidably fitted into the adjusting member,
A first spring is provided between one of the spring receiving plates located in the atmospheric chamber and the diaphragm, and a second spring is provided between the other of the spring receiving plates and the second adjustment member. Features.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Reference numeral 1 denotes a housing divided into left and right halves, and a diaphragm 2 is inserted between the connecting end of the right bowl-shaped body 1 ₁ and the left bowl-shaped body 1 ₂ . The outer peripheral bead is clamped, thereby dividing the inside of the housing 1 into an atmospheric chamber A and an operating pressure chamber B. The operating rod 3 made of a threaded rod is connected to the atmospheric chamber A.
The diaphragm 2 is connected to the center of the diaphragm 2 through a through hole 5 provided in the side wall 4 of the diaphragm 2 . A connecting rod 6 is connected to the free end of the operating rod 3, and the connecting rod 6 is connected to an ignition interrupter (not shown) to operate it.

A threaded cylindrical first adjusting member 7 having a nut-like operating portion 7a is screwed onto the operating rod 3 so as to be adjustable in forward and backward movement, and both ends of the member 7 face the inside and outside of the through hole 5. Further, a second adjusting member 8 consisting of a nut located outside the through hole 5 is screwed onto the operating rod 3 so as to be adjustable in forward and backward directions.

A flange-shaped interval retaining piece 7b is protruded from the middle part of the outer peripheral surface of the first adjusting member 7, and the interval retaining piece 7b
A pair of spring receiving plates 9 ₁ and 9 ₂ facing each other with the side wall 4 of the atmospheric chamber A in between are slidably fitted onto the outer peripheral surface of the first adjustment member 7 .

A first spring 101 is compressed between one spring receiving plate ₉₁ and the diaphragm 2, and the other spring receiving plate ₉₁ is compressed.
_A second spring ₁₀₂ is compressed between the spring receiving plate ₉₃ and the second adjusting member 8. At both ends of the first adjustment member 7, stop rings 11 ₁ and 11 ₂ are fitted, respectively, to restrict the retard angle and advance angle movement limits of the operating rod 3.

The working pressure chamber B is connected to the positive pressure source 1 via the switching valve 12.
3 and a negative pressure source 14.

In the illustrated example, the first spring ₁₀₁ determines the movement of the operating rod 3 in the retard direction, that is, the leftward movement start pressure when positive pressure is introduced into the operating pressure chamber B.
The set load is adjusted by rotating the operating portion 7a of the first adjusting member 7 to move it forward or backward. On the other hand, the second spring ₁₀₂ determines the movement of the operating rod 3 in the advance direction when negative pressure is introduced into the operating pressure chamber B, that is, the rightward movement start pressure, and its set load is applied to the second adjusting member 8. It is adjusted by rotating it and moving it forward and backward. After adjusting the set load of each spring 10 ₁ , 10 ₂ , the first and second adjustment members 7 and 8
is fixed to the operating rod 3 with adhesive or the like. On the inner and outer surfaces of the side wall 4 of the atmospheric chamber A are spring receiving plates 9 ₁ , 9 _{2 .}
First and second guide tubes 15 ₁ , _{15 2} are protrudingly provided to surround the spring receiving plates 9 ₁ , _{9 2 .}
movement in the retard and advance directions is performed smoothly.

Next, the operation of this embodiment will be explained.
The state shown in FIG. 1 shows the state in which the diaphragm 2 and therefore the operating rod 3 are in a neutral position.

Here, when the engine enters an idling or deceleration state, the switching valve 12 is switched to the positive pressure source 13 side, and positive pressure is introduced into the working pressure chamber B.
When the positive pressure overcomes the set load of the first spring ₁₀₁ , the first spring ₁₀₁ contracts and moves the operating rod 3 to the left, as shown in FIG. 2, thereby operating the interrupter and igniting. delay the time. The second spring ₁₀₂ has a spring receiving plate ₉₂ that is connected to the spacing retaining piece 7 of the first adjusting member 7.
Since it is pushed by b, it moves to the left together with the operating rod 3 while keeping the set load at neutral. The left movement limit of the operating rod 3 is
Since one stop ring ₁₁₁ is restricted at the position where it abuts against the spring receiving plate ₉₁ , the retard angle by the interrupter is maintained at a constant angle.

Next, when the engine enters high-output operation, the switching valve 12 is switched to the negative pressure source 14 side, and negative pressure is introduced into the working pressure chamber B. When the negative pressure overcomes the set load of the second spring ₁₀₂ , the second spring ₁₀₂ contracts and moves the operating rod 3 to the right, as shown in FIG. 3, thereby operating the interrupter and igniting. Advance the timing. The first spring ₁₀₁ has its spring receiving plate ₉₁ connected to the first spring 101.
Since it is pushed by the spacing holding piece 7b of the adjustment member 7, it moves to the right together with the operating rod 3 while maintaining the set load at neutral. The rightward movement limit of the operating rod 3 is restricted at the position where the other stop ring ₁₁₂ abuts against the spring receiving plate ₉₂ , so the advance angle by the interrupter is maintained at a constant angle.

By the way, the present invention can also be applied to an internal combustion engine with a turbocharger, and in this case, for example, if the working pressure chamber B is connected to the downstream side of the compressor in the intake pipe, it is possible to apply the pressure chamber B to the intake pipe downstream of the compressor. When the compressor is not operating, negative pressure is introduced into the operating pressure chamber B to advance the ignition timing, while when the engine is at high output, that is, when the compressor is operating, positive pressure is introduced into the operating pressure chamber B to retard the ignition timing. be able to.

As described above, according to the present invention, the inside of the housing 1 is divided into the atmospheric chamber A which is constantly communicated with the atmosphere by the diaphragm 2, and the working pressure chamber B in which the introduced pressure can be switched to positive pressure or negative pressure, and the A first adjustment member 7 that connects an actuating rod 3 that passes through a through hole 5 provided in the side wall 4 of the chamber A to the diaphragm 2, and has both ends of the actuating rod 3 facing inside and outside of the through hole 5.
and a second adjusting member 8 located outside the through hole 5 is screwed together so that it can be adjusted forward and backward, and the first adjusting member 7 has a spacing holding piece 7b protruding from the middle part of the first adjusting member 7; A pair of spring receiving plates 9 ₁ and 9 ₂ facing each other with the side wall 4 in between are slidably fitted, and between one of the spring receiving plates 9 ₁ located in the atmospheric chamber A and the diaphragm 2. Since the first spring ₁₀₁ is compressed and the second spring ₁₀₂ is compressed between the other spring receiving plate ₉₂ and the second adjusting member 8, the first spring 101 is compressed.
The second adjustment members 7 and 8 can be operated on one side outside the housing 1, making it easy to operate them and efficiently adjusting the set loads of the springs 10 ₁ and 10 ₂ . Furthermore, since the first and second adjustment members 7 and 8 are arranged on the atmospheric chamber A side, and no member to be operated is arranged inside the working pressure chamber B, the sealing performance of the working pressure chamber B is good. This prevents air pressure leaks and allows the device to operate accurately at all times.

[Brief explanation of the drawing]

The drawings show an embodiment of the device of the present invention, in which Fig. 1 is a longitudinal side view of the neutral state, Fig. 2 is a longitudinal side view of the main part in the retarded state, and Fig. 3 is a main part in the advanced state. FIG. A... Atmospheric chamber, B... Operating pressure chamber, 1... Housing, 2... Diaphragm, 3... Operating rod, 4
...Side wall, 5...Through hole, 7...First adjustment member, 7
b... Spacing piece, 8... Second adjustment member, 9 ₁ ,
9 ₂ ... Spring receiving plate, 10 ₁ ... First spring, 10 ₂
...Second spring, 12...Switching valve, 13...Positive pressure source, 14...Negative pressure source.

Claims (1)

[Claims] 1 The interior of the housing 1 is divided by a diaphragm 2 into an atmospheric chamber A, which is always in communication with the atmosphere, and an operating pressure chamber B, in which the introduced pressure can be switched between positive pressure or negative pressure, and a transparent An actuating rod 3 passing through the hole 5 is connected to the diaphragm 2, and the actuating rod 3 has a first adjusting member 7 whose both ends face the inside and outside of the through hole 5, and a second adjusting member 7 located outside the through hole 5. The adjustment member 8 is screwed together so that it can be adjusted forward and backward, and the first
A spacing retaining piece 7b protruding from the intermediate portion of the first adjusting member 7 and a pair of spring receiving plates 9 ₁ and 9 ₂ facing each other across the side wall 4 are slidably fitted into the adjusting member 7, A first spring 101 is placed between one of the spring receiving plates ₉₁ located in the atmospheric chamber A and the diaphragm 2, and a first spring ₁₀₁ is placed between the other spring receiving plate ₉₂ and the second adjusting member 8. An ignition timing control device for an internal combustion engine in which two springs 10 _{and 2} are compressed.