JP4389187B2 - Inlet throttle valve sticking prevention device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for fixing an intake throttle valve at a position slightly opened from an idle position when the engine is stopped, and preventing a valve plate from sticking to an intake pipe wall.
[0002]
[Prior art]
When the intake throttle valve is placed in the idle position, which is the fully closed angle when the engine is stopped, if the carbon, oil, tar, etc. are attached to the valve plate and the intake pipe wall, these will solidify and intake the valve plate It sticks to the pipe wall, causing a situation that the valve is not open or cannot be opened during the next engine operation.
[0003]
As a countermeasure, there is one in which a sticking prevention device is provided on an intake throttle valve of an automobile engine. In this sticking prevention device, as shown in FIG. 4, an actuator 56 is disposed on the opposite side of the valve shaft 52 with the idle position adjusting screw 55 of the lever 54 fixed to the valve shaft 52 of the intake throttle valve 51.
[0004]
An actuator 56 communicates a negative pressure chamber 59 on one side of a diaphragm 58 having a rod 57 coupled to the center thereof with a portion downstream of the intake throttle valve 51 of the intake pipe 50 by a conduit 61 and a pressing spring 60 comprising a compression coil spring. This is a negative pressure type actuator in which the negative pressure chamber 59 is charged and the diaphragm 58 is urged.
[0005]
Then, during engine operation, a negative pressure generated downstream of the intake throttle valve 51 is introduced into the negative pressure chamber 59 to displace the diaphragm 58, thereby separating the rod 57 from the lever 54, and the valve plate 53 as shown in FIG. The engine is rotated from the idle position shown in (A) to the fully opened position, and the intake control according to the accelerator operation is performed as usual. Since the negative pressure disappears when the engine is stopped, the diaphragm 58 is pressed and displaced by the push spring 60, the rod 57 is brought into contact with the lever 54 and rotated, and the valve plate 53 is moved to the idle position as shown in FIG. Fix it in a slightly open position.
[0006]
[Problems to be solved by the invention]
In the above-described sticking prevention device including the negative pressure type actuator 56 using the diaphragm 58, when the diaphragm 58 is damaged, the atmosphere flows into the negative pressure chamber 59 from the damaged portion, so that negative pressure is applied to the diaphragm 58. The rod 57 does not act, and the rod 57 is pushed by the push spring 60 to rotate the lever 54, and the valve plate 53 cannot be closed from the position slightly opened from the idle position to the idle position.
[0007]
Therefore, if the diaphragm 58 is damaged while the vehicle is running, it cannot be stopped unless emergency evacuation means such as turning off the key switch or hitting the vehicle body against an obstacle is taken. Also, if the diaphragm 58 is damaged while the engine is stopped or immediately after starting, idle rotation cannot be performed, and even when the accelerator pedal is released, the rotational speed increases, causing high noise, Starting it will cause a runaway.
[0008]
The present invention has a negative pressure type actuator using a diaphragm provided to prevent sticking of the intake throttle valve, it becomes impossible to return to the idle position when the diaphragm is damaged, causing the vehicle to run away. The present invention has been made to solve the above-mentioned problem, and aims to be able to return to the idle position even if the diaphragm is damaged, and thus to ensure the safety of the automobile and the occupant. .
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention, the actuator has a negative pressure chamber and a compression spring which negative pressure is introduced for generating the intake throttle valve downstream of the diaphragm and the intake pipe that combines rods, and the intake throttle e ingredients lever secured to the valve shaft of the valve, the lever and the side edges idle position adjusting screw hits across the valve shaft, the opposite direction of the inclination direction of the valve plate in the idle position to the side edges of the symmetric part a receiving edge tailored towards wrote to the actuator as well as the inclination to, provided with protrusions at the tip of the receiving edge continuously, and rotated in the intake pipe by support shaft between the lever and the actuator capable and the pressure lever is installed with bell crank action having an action part toward the support is not said actuator and lever action of the actuator side of the pressing lever There has pin-like contact piece in contact with the receiving edge formed on this lever action of the lever-side with and is rotatably supported on the tip of the rod of said actuator, said push when the engine is stopped A spring presses and displaces the diaphragm, and the rod rotates the lever via the pressing lever to fix the intake throttle valve at a position slightly opened from the idle position. Negative pressure allowed the intake throttle valve to return to the idle position by sucking and displacing the diaphragm, and when the engine stopped, the contact piece engaged with the protrusion and opened the intake throttle valve slightly from the idle position. located in fixed, the diaphragm of the actuator is damaged during engine operation, air is flow from the air chamber of the actuator to the negative pressure chamber To when the tip of the negative pressure chamber atmosphere is introduced pressing lever protrudes than a predetermined, in the case of wide open throttle valve, the contact piece and the receiving engagement is disengaged by lever projections above the edge Positioned outside the movement locus of the contact piece accompanying the rotation of the pressing lever, the pressing spring extends greatly to further rotate the pressing lever so that the contact piece moves over the protrusion .
[0010]
When the negative pressure on the downstream side of the intake throttle valve normally acts on the diaphragm, the pressing lever can be rotated in the direction to release the contact piece from the lever, and the intake throttle valve can be returned to the idle position. It is essentially the same.
[0011]
However, when the negative pressure no longer acts due to the diaphragm being damaged, the intake throttle valve is largely opened by the accelerator operation and then returned. By this opening operation, the engagement between the contact piece and the protrusion is disengaged, the push spring expands greatly, the pressing lever is further rotated, and the contact piece moves to a position over the protrusion. Therefore, when the accelerator is released, the lever is not stopped by the contact piece, and the intake throttle valve can return to the idle position. As a result, the object of preventing the vehicle from running away and ensuring safety is achieved.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. An intake throttle valve 2 having a disc-like valve plate 3 fixed to a valve shaft 4 is provided in an intake pipe 1. As is well known, an accelerator means and a valve closing spring (not shown) are opened and closed between an idle position and a fully open position.
[0013]
A lever 6 is fixed to a portion of the valve shaft 4 protruding from the intake pipe 1, and this lever 6 hits the idle position adjusting screw 5 to define the idle opening of the intake throttle valve 2. Further, the side edge of the lever 6 on which the idle position adjusting screw 5 abuts and the side edge of the symmetrical portion is a receiving edge 7 inclined in the direction opposite to the inclination direction of the valve plate 3 in the idle position. And a protrusion 8 is provided at the tip thereof.
[0014]
On the other hand, an actuator 11 is installed on the outer side of the intake pipe 1 so as to face the receiving edge 7. The actuator 11 includes a negative pressure chamber 13 and an atmospheric chamber 14 that are airtightly partitioned by a diaphragm 12, a compression spring 15 that is a compression coil spring that is inserted into the negative pressure chamber 13 and biases the diaphragm 12, and the center of the diaphragm 12. And a rod 16 projecting outside through the atmosphere chamber 14. The downstream portion of the intake throttle valve 2 of the intake pipe 1 and the negative pressure chamber 13 communicate with each other by a conduit 17.
[0015]
A pressing lever 22 is installed between the lever 6 and the actuator 11 so that the suction pipe 1 is rotatably supported by the support shaft 21. The pressing lever 22 is coupled to the tip of the rod 16. A pin-shaped contact piece 23 is also provided.
[0016]
FIG. 1 shows a state when the engine is idling. A high negative pressure generated on the downstream side of the intake throttle valve 2 of the intake pipe 1 is introduced into the negative pressure chamber 13 through the conduit 17 so that the diaphragm 12 is The suction lever 22 is sucked and displaced toward the negative pressure chamber 13 to rotate the pressing lever 22 in the clockwise direction in the drawing, and the contact piece 23 is separated from the receiving edge 7 and is retracted to a position not in contact with the lever 6.
[0017]
For this reason, the intake throttle valve 2 is a pressing lever from the idle position shown in FIG. 1 where the lever 6 hits the idle position adjusting screw 5 by the valve closing spring until the valve plate 3 rotates clockwise in the drawing to reach the fully open position. 22 can operate without being interfered with.
[0018]
Next, since the negative pressure chamber 13 becomes atmospheric pressure when the engine is stopped, the diaphragm 12 is pressed and displaced toward the atmospheric chamber 14 by the pressing spring 15 and the pressing lever 22 is rotated counterclockwise in the drawing. At this time, the contact piece 23 contacts the receiving edge 7 and moves while sliding, thereby pressing and rotating the lever 6 in the clockwise direction in the drawing. For this reason, the intake throttle valve 2 that has returned to the idle position when the engine is stopped moves again in the opening direction, and when the contact piece 23 is engaged with the protrusion 8 at the tip of the receiving edge 7, the pressure displacement of the diaphragm 12 is reduced. Stop.
[0019]
This state is shown in FIG. 2, and by setting the pressing force applied to the contact piece 23 by the pressing spring 15 to be larger than the counterclockwise rotational force of the lever 6 by the valve closing spring, the intake throttle valve 2 is set. Is fixed at a position slightly opened from the idle position. At this time, the pressing spring 15 is not fully extended, and is in a half-compressed state, that is, in a state having a margin on the extending side.
[0020]
In this way, when the engine is stopped, the outer peripheral edge of the valve plate 3 is placed at a position far away from the pipe wall of the intake pipe 1, so that carbon, oil, tar, etc. are attached to the valve plate and the intake pipe wall. However, the inconvenience that these solidify and stick the valve plate 3 to the pipe wall of the intake pipe 1 is avoided. Therefore, an engine system including an exhaust gas recirculation system in which exhaust gas containing carbon and oil enters the intake pipe 1 and a blow-by gas system in which unburned gas containing oil enters the intake pipe 1 and an LPG containing tar content are included. In the engine system that uses fuel, the sticking of the valve plate 3 of the intake throttle valve 2 to the intake pipe wall is reliably prevented, and the accelerator does not occur during the next engine operation without causing valve opening failure or valve opening failure. Intake control according to operation can be performed.
[0021]
In the unlikely event that the diaphragm 12 is damaged, the atmosphere flows into the negative pressure chamber 13 from the damaged portion 12 _a shown in FIG. 3 so that no negative pressure acts on the diaphragm 12, and the diaphragm 12 is It is pressed and displaced toward the atmosphere chamber 14.
[0022]
When the diaphragm 12 is damaged while the vehicle is running, the intake throttle valve 2 is opened considerably wide, so that the protrusion 8 of the lever 6 is positioned outside the movement locus of the contact piece 23 as the pressing lever 22 rotates. For this reason, the rod 16 is pushed to the limit of extension of the push spring 15 and the push lever 22 is largely rotated to a position where the contact piece 23 exceeds the protrusion 8. For this reason, when the accelerator is released, the lever 6 returns to the idle position without hitting the contact piece 23 as shown in FIG. 3, and the vehicle can be stopped and the engine can be further stopped. In addition, the vehicle can be restarted and the engine can be restarted as usual.
[0023]
When the diaphragm 12 is damaged while the engine is stopped, immediately after starting, or during idle operation, the pressing lever 22 is rotated by the pressing spring 15 until the contact piece 23 comes into contact with the protrusion 8, which is the same as shown in FIG. It becomes positional relationship. For this reason, since the engine is idling at a high speed, the driver senses and applies the accelerator operation, and takes measures to open the intake throttle valve 2 once and release the accelerator. By this operation, the protrusion 8 of the lever 6 is separated from the contact piece 23, the pressing lever 22 is rotated to the limit of extension of the pressing spring 15, and the contact piece 23 moves to a position beyond the protrusion 8. Therefore, when the accelerator is released, the lever 6 returns to the idle position without hitting the contact piece 23, and is in the state shown in FIG.
[0024]
Thus, no matter what point the diaphragm 12 is damaged, the intake throttle valve 2 can be returned to the idle position for safety. The receiving edge 7 and the protrusion 8 are provided on the lever for setting the idle position. However, the receiving edge 7 and the protrusion 8 may be provided on a separate dedicated lever.
[0025]
【The invention's effect】
As described above, according to the present invention, when the engine is stopped, the diaphragm of the negative pressure actuator that prevents the valve plate from sticking to the intake pipe wall by fixing the intake throttle valve at a position slightly wider than the idle position should be damaged. In this case, the inconvenience that the intake throttle valve does not return to the idle position is solved, and the vehicle can be prevented from running away and can be operated safely, and the vehicle can be stopped and the engine stopped and restarted without any trouble. It is something that can be done.
[Brief description of the drawings]
FIG. 1 is a partially cutaway front view in a state during idle operation according to an embodiment of the present invention.
FIG. 2 is a partially cutaway front view of the embodiment shown in FIG. 1 when the engine is stopped.
FIG. 3 is a partially cutaway front view of the embodiment of FIG. 1 when the diaphragm is broken.
4A is a partially cutaway front view of the conventional example when the engine is operating and FIG. 4B is when the engine is stopped.
[Explanation of symbols]
1 intake pipe, 2 intake throttle valve, 4 valve shaft, 6 lever, 7 receiving edge, 8 projection, 11 actuator, 12 diaphragm, 13 negative pressure chamber, 15 push spring, 16 rod, 22 pressure lever, 23 contact piece

Claims (1)

The actuator has a negative pressure chamber and a compression spring which negative pressure generated in the intake throttle valve downstream of the diaphragm and the intake pipe attached rod is introduced, and e ingredients a lever which is fixed to the valve shaft of the throttle valve , receiving the lever tailored towards wrote to the actuator as well as slope and side edges idle position adjusting screw hits across the valve axis, the inclination direction opposite to the direction of the valve plate in the idle position to the side edges of the symmetric part and the edge is provided continuously protrusion and is at the tip of the receiving edge, and is between the lever and the actuator toward the said actuator and lever is rotatably supported in the intake pipe by a support shaft A pressure lever having a bell crank action with a working part is installed, and the action part on the actuator side of the pressure lever is the tip of the rod of the actuator Has a pin-like contact piece in contact with the receiving edge formed on this lever action of the lever-side with and is rotatably supported, the push spring to press displacing the diaphragm when the engine is stopped Thus, the rod rotates the lever through the pressing lever to fix the intake throttle valve at a position slightly opened from the idle position, and the negative pressure in the negative pressure chamber sucks and displaces the diaphragm during engine operation. allow to return the intake throttle valve to the idle position by the contact piece when the engine is stopped is the projection engages fixed in the open position a little than the idle position the intake throttle valve, when the engine operation actuator diaphragm is damaged, the air from the air chamber of the actuator to the negative pressure chamber is introduced atmospheric air in the negative pressure chamber flows pressed Les When the tip of the over is projected than the predetermined movement locus of the case where the wide open throttle valve, the contact piece and the receiving contact piece lever projections out of engagement with the edge due to the rotation of the pressing lever The sticking prevention device is characterized in that the contact spring moves over to the position where the contact piece has moved over the protrusion, with the push spring extending greatly and the pressing lever further rotated .

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