JPH0435557Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a safety device for preventing a vehicle from running out of control when an actuator failure occurs in an engine control valve mechanism in which a throttle valve is driven by an actuator.

[Description of Prior Art] The throttle valve of the conventional engine control valve mechanism is
The vehicle is operated by a mechanism that is linked to the accelerator pedal, and if this accelerator pedal linkage mechanism fails during high-speed driving, it becomes impossible to reduce the speed of the vehicle, leading to traffic accidents.

To solve this problem, for example, as shown in Utility Model Publication No. 48-20168, two throttle valves are provided in the intake passage, and each throttle valve is opened at the same angle. An interlocking mechanism is provided for each throttle valve, so that even if one interlocking mechanism fails and the throttle valve is left open, the intake mixture amount can be adjusted using the other throttle valve. things are provided.

Recently, instead of opening and closing the throttle valve using a conventional accelerator pedal interlocking mechanism, an electronic control circuit calculates the amount of depression of the accelerator pedal, and the electronic control circuit operates an actuator to open and close the throttle valve. A device that opens and closes a valve is used. Such an actuator that opens and closes the throttle valve also requires a safety device in case the actuator fails, but the conventional double accelerator pedal interlocking mechanism cannot be applied. Furthermore, since the accelerator pedal interlocking mechanism has a large number of component parts, providing two accelerator pedal interlocking mechanisms has the disadvantage of increasing costs.

[Problems to be solved by the invention] The present invention has been made in view of the above points.In the engine control valve mechanism in which the throttle valve is actuated by the actuator, when a failure occurs in the actuator, the throttle valve is The purpose of this is to prevent the vehicle from running out of control by restricting the amount of intake air with a separate valve, and to eliminate the risk of malfunction that would occur if the valve were to limit the amount of intake air during normal operation.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an engine in which an actuator is controlled by an electronic control circuit, the actuator operates a throttle valve, and the actuator is controlled by the electronic control circuit. In the control valve mechanism, a negative pressure chamber is divided by a diaphragm and communicates with the downstream side of the intake passage, a valve that changes the cross section of the intake passage in conjunction with the diaphragm, and a valve that is operated by the electronic control circuit during normal operation. A switching means for introducing intake passage negative pressure into the negative pressure chamber and introducing atmospheric air into the negative pressure chamber in the event of actuator failure, and a negative pressure chamber side of the diaphragm and members other than the diaphragm forming the negative pressure chamber. a magnet attached to at least one side of the diaphragm, and a spring provided in a negative pressure chamber to bias the diaphragm in a direction opposite to the negative pressure chamber, and when the actuator is in normal operation, the diaphragm is The valve is held at a fixed position close to a member other than the diaphragm to prevent it from protruding into the intake passage, and when the actuator fails, atmospheric air is introduced into the negative pressure chamber and the valve narrows the cross section of the intake passage. It is something.

[First example] Next, the present invention will be explained based on the drawings.

FIG. 1 is a system diagram showing an embodiment of a safety device for an actuator-driven throttle valve according to the present invention. The opening degree of a throttle valve 12 provided in an intake passage 10 of an engine control valve mechanism is operated by an actuator 14 . The actuator 14 is controlled by an electronic control circuit 16 that calculates the amount of depression of the accelerator pedal.

In the intake passage 10, a piston valve 18 that changes the cross section of the intake passage is provided upstream or downstream of the throttle valve 12 position. One end of the piston valve 18 is attached to a diaphragm 24 whose peripheral edge is fixed to the body 20 and cover 22 of the engine control valve mechanism. This diaphragm 24 and the body 20 of the engine control valve mechanism form an atmospheric chamber 26, and this diaphragm 2
4 and the cover 22 form a negative pressure chamber 28. The negative pressure chamber 28 is supplied with intake passage negative pressure from a negative pressure passage 30 communicating with a position downstream of the throttle valve 12 in the intake passage 10, or from an atmospheric passage 32.
Either atmospheric air from the air is introduced through a three-way valve 34 as a switching means. This three-way valve 34 is controlled by the electronic control circuit 16, and allows the negative pressure chamber 28 and the negative pressure passage 30 to communicate unless a failure occurs in the actuator 14. If a failure occurs in the actuator 14, for example, if the maniboost is abnormally large or the engine speed does not drop even though the accelerator pedal is at the idling position, the maniboost, engine speed, etc. The value of the parameter is determined by the electronic control circuit 16, the three-way valve 34 is switched, and the atmospheric passage 32 is communicated with the negative pressure chamber 28.

A spring 36 is provided in the negative pressure chamber 28 to constantly press the diaphragm 24 toward the atmospheric chamber 26 . A permanent magnet 38 is attached to the negative pressure chamber 28 side of the diaphragm 24, while a permanent magnet 40 having a different magnetic pole from the permanent magnet 38 is attached to the negative pressure chamber 28 side of the cover 22.

[Function] In the above configuration, if there is no failure in the actuator 14, the negative pressure chamber 28 is connected to the negative pressure passage 30.
Since the engine is in communication with the engine, intake negative pressure is introduced into the negative pressure chamber 28 after startup. As a result, diaphragm 2
4 is drawn to the negative pressure chamber 28 side, and the piston valve 18
is pulled upward in Figure 1. When the diaphragm 24 moves toward the negative pressure chamber 28, the permanent magnets 38 and 40 approach and attract each other. That is, the diaphragm 24 is pulled upward in FIG.
It is kept from protruding inside. Due to the attractive force of the permanent magnets 38 and 40, the piston valve 18 is maintained in a state in which it does not protrude into the intake passage 10 even if there is some fluctuation in the intake negative pressure. When the engine is stopped and the pressure in the intake passage 10 becomes atmospheric pressure, the force of the spring 36 overcomes the attractive force of the permanent magnet, and the piston valve 18 protrudes into the intake passage 10.

Next, when a failure occurs in the actuator 14, the electronic control circuit 16 switches the three-way valve 34 to communicate the atmospheric passage 32 with the negative pressure chamber 28, and the inside of the negative pressure chamber 28 becomes atmospheric pressure. As a result, the spring 36 moves the diaphragm 24 toward the atmospheric chamber 26 against the attractive force of the permanent magnet, causing the piston valve 18 to protrude into the intake passage 10.

[Effects of the invention] As described above, in the present invention, when a failure occurs in the actuator 14, the piston valve 18 protrudes into the intake passage 10, significantly reducing the amount of intake air flowing inside the intake passage 10. . Therefore, even if the actuator 14 fails while the throttle valve 12 is open, the piston valve 18
By limiting the amount of intake air, the speed of the vehicle etc. is automatically reduced, making it possible to prevent accidents due to runaway vehicles.

Note that a magnet may be attached only to either the negative pressure chamber 28 side of the diaphragm 24 or the negative pressure chamber 28 side of the cover 22, and a metal to which the magnet attracts may be attached to the other side.

[Second Embodiment] Next, another embodiment of the present invention is shown in FIG. 1st
The same reference numerals as in the figure indicate the same parts. A butterfly valve 42 is rotatably installed in the intake passage 10 upstream or downstream of the throttle valve 12 position. A lever 46 is fixed to the rotating shaft 44, and a rod 48 fixed to the diaphragm 24 is pivotally connected to the tip of the lever 46.

Further, as in the first embodiment, a spring 36 is provided in the negative pressure chamber 28 to constantly press the diaphragm 24 toward the atmospheric chamber 26, a permanent magnet 38 is attached to the negative pressure chamber 28 side of the diaphragm 24, and a Pressure chamber 28
A permanent magnet 4 with a magnetic pole different from that of the permanent magnet 38 is placed on the side.
Even with the above configuration, if there is no failure in the actuator 14, the intake negative pressure is introduced into the negative pressure chamber 28 after startup, the diaphragm 24 is drawn toward the negative pressure chamber 28, and the permanent magnet 38 and permanent magnet 4
0 attract each other. That is, permanent magnets 38, 4
Due to the suction force of 0, the piston valve 18 is maintained in a state in which it does not protrude into the intake passage 10 even if there are some fluctuations in the intake negative pressure.

Here, if a failure occurs in the actuator 14, the atmospheric passage 32 is communicated with the negative pressure chamber 28,
The diaphragm 24 is connected to the air chamber 26 by the spring 36.
pushed to the side. As a result, the butterfly valve 42 rotates in a direction that narrows the cross section of the intake passage, thereby limiting the amount of intake air, and as in the previous embodiment, it is possible to eliminate the risk of the vehicle running out of control.

[Third Embodiment] Next, another embodiment of the present invention is shown in FIG.
The same reference numerals as in FIGS. 1 and 2 indicate the same parts. 1st,
In the embodiment shown in FIG. 2, a three-way valve 34 switches between a negative pressure passage 30 and an atmospheric passage 32.
Negative pressure or atmospheric pressure was introduced into the negative pressure chamber 28. However, in this embodiment, a negative pressure passage 50 and an atmospheric passage 52 are separately communicated with the negative pressure chamber 28. The negative pressure passage 50 is always in communication with the negative pressure chamber 28, but the atmospheric passage 52 is connected to the electronic control circuit 1.
It is opened and closed by a solenoid 54 as a switching means operated by a switch 6. This solenoid 54 normally closes the atmospheric passage 52 and opens the atmospheric passage 52 when a failure occurs in the actuator 14.

Further, as in the first embodiment, a spring 36 is provided in the negative pressure chamber 28 to constantly press the diaphragm 24 toward the atmospheric chamber 26, a permanent magnet 38 is attached to the negative pressure chamber 28 side of the diaphragm 24, and a Pressure chamber 28
A permanent magnet 4 with a magnetic pole different from that of the permanent magnet 38 is placed on the side.
Even with the above configuration, if there is no failure in the actuator 14, the intake negative pressure is introduced into the negative pressure chamber 28 after startup, the diaphragm 24 is drawn toward the negative pressure chamber 28, and the permanent magnet 38 and permanent magnet 4
0 attract each other. That is, permanent magnets 38, 4
Due to the suction force of 0, the piston valve 18 is maintained in a state in which it does not protrude into the intake passage 10 even if there are some fluctuations in the intake negative pressure.

Here, if a failure occurs in the actuator 14, atmospheric air is introduced into the negative pressure chamber 28, and as a result, the butterfly valve 42 rotates in a direction to narrow the cross section of the intake passage to limit the amount of intake air. As in the example, it is possible to prevent accidents caused by runaway vehicles and the like.

As described above, according to the safety device for an actuator-driven throttle valve according to the present invention, when the actuator is in normal operation, negative pressure is introduced into the negative pressure chamber and the diaphragm is held at a fixed position by the action of the magnet. To prevent the valve from protruding into the intake passage even if the intake passage negative pressure fluctuates. On the other hand, when the actuator fails, the electronic control circuit narrows the cross section of the intake passage using a valve other than the throttle valve to reduce the amount of intake air.This prevents the vehicle from running out of control when the actuator fails. , which can eliminate the risk of accidents occurring.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are system diagrams showing embodiments of a safety device for an actuator-driven throttle valve according to the present invention. 10... Intake passage, 12... Throttle valve, 14... Actuator, 16... Electronic control circuit, 18... Piston valve, 24... Diaphragm, 28... Negative pressure chamber, 30, 50... Negative pressure Passage, 32, 52...Atmospheric passage, 34...Three-way valve,
36... Spring, 38, 40... Magnet.

Claims (1)

[Scope of utility model registration request] The actuator is controlled by an electronic control circuit, and the actuator operates the throttle valve.
In an engine control valve mechanism in which the actuator is controlled by an electronic control circuit, a negative pressure chamber is defined by a diaphragm and communicates with the downstream side of the intake passage, a valve that changes the cross section of the intake passage in conjunction with the diaphragm, and the electronic switching means operated by a control circuit to introduce intake passage negative pressure into the negative pressure chamber during normal operation and to introduce atmospheric air into the negative pressure chamber when the actuator fails; It has a magnet attached to at least one side of a member other than the diaphragm that forms the negative pressure chamber, and a spring provided in the negative pressure chamber that biases the diaphragm in a direction opposite to the negative pressure chamber, and the actuator is operated normally. At times, the diaphragm is held in a fixed position close to members other than the diaphragm by the action of the magnet to prevent the valve from protruding into the intake passage, and when the actuator fails, atmospheric air is introduced into the negative pressure chamber to close the valve. A safety device for an actuator-driven throttle valve, which is characterized by narrowing the cross section of the intake passage.