JPS635569B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a throttle valve opening control device that includes a diaphragm device and controls the throttle valve opening of an engine using the diaphragm device. The present invention relates to a control device that controls the pressure acting on a negative pressure chamber of a diaphragm device in order to set the opening degree of a throttle valve according to conditions.

[Conventional technology]

In recent years, more and more vehicles are being equipped with air conditioners to improve driving comfort, and with power steering systems that reduce the steering load to improve maneuverability.

When equipped with an air conditioner or power steering, it is necessary to install a compressor to improve the cooling capacity of the air conditioner and an oil pump to drive the power steering, and these compressors and oil pumps are driven by the rotational power of the engine. It has a structure.

When such components, so-called auxiliary equipment, are installed, the load for driving the compressor and oil pump acts on the engine, which can lower the engine speed, especially during idling, and cause idling instability. In extreme cases, this may cause the engine to stall.

Therefore, in order to avoid idle instability and engine stall caused by driving these accessories, a throttle valve opening control device has been developed that increases the opening of the throttle valve to increase the idle rotation speed when driving the accessories. , an idle-up device is used (for example, Utility Model Application Publication No. 54-010124 and Utility Model Application Publication No. 52-01).
Publication No. 128835).

According to the above-mentioned conventional idle-up device, atmospheric pressure is applied to the negative pressure chamber of the diaphragm device, which is equipped with a rod that comes into contact with the throttle valve lever that rotates integrally with the throttle valve, in response to the input of the air conditioner operation signal. By opening the valve a predetermined opening larger than the idling opening, it is possible to suppress a decrease in the rotational speed, thereby solving the above-mentioned problems.

In addition, in these idle-up devices, the diaphragm device has a dart pot function that gradually closes the throttle valve, and by suppressing the sudden closing of the throttle valve during deceleration, it improves deceleration feeling and exhaust gas purification performance. It is something that can be improved.

Furthermore, in order to reduce the number of engine components, simplify the device, and reduce costs, it is also possible to use the above-mentioned diaphragm device to improve warm-up performance during cold conditions. By opening the throttle valve a predetermined opening larger than the idle opening for a predetermined period of time after a cold start,
Components such as exhaust catalysts that are installed in the exhaust passage downstream of the engine combustion chamber by increasing the amount of fuel supplied from the carburetor to stabilize engine rotation after starting, and by supplying a rich mixture. warm-up can be promoted.

[Problem that the invention seeks to solve]

However, in the above conventional throttle valve opening control device including the diaphragm device, it is not always possible to set the throttle valve opening to a desired opening depending on various conditions of the engine.

In other words, as mentioned above, the throttle valve opening required to suppress the decrease in engine speed due to driving of auxiliary equipment such as the air conditioner and oil pump, and the throttle valve opening required at the time of cold start are as follows. It doesn't necessarily match. In other words, after a cold start, it is preferable to raise the temperature of the engine cooling water and exhaust catalyst as quickly as possible, and also to increase the throttle valve opening as much as possible from the viewpoint of exhaust purification.
It is necessary to set the time required for so-called first idle to be short.

On the other hand, the idle up after warming up,
In other words, the throttle valve opening to compensate for the drop in idle speed due to auxiliary equipment drive must be kept as small as possible in consideration of the noise generated by the engine and the improvement of fuel efficiency. It is not preferable to set the opening to be the same as the throttle valve opening.

However, in the conventional device described above, a constant pressure, that is, atmospheric pressure, acts on the negative pressure chamber of the diaphragm device in order to increase the throttle valve opening, so the throttle valve opens as the idle increases. The degree remains constant. Therefore, if the throttle valve opening after warming up is set to the opening when cold,
The opening degree of the throttle valve is too large, causing noise as the engine speed increases and fuel consumption worsening as the amount of fuel consumed increases. Furthermore, if the opening of the throttle valve during cold conditions is made to match the opening after warming up, the opening of the throttle valve during cold conditions will be too small and the amount of fuel supplied will decrease, resulting in the so-called first idle. This may result in unstable rotation at times, and it takes too much time for the exhaust catalyst etc. to be sufficiently warmed up, resulting in deterioration of exhaust purification performance.

Therefore, the present invention sets the throttle valve opening according to various engine conditions regardless of operating conditions such as when cold or after warming up, thereby improving idle stability and fuel efficiency and suppressing noise generation. The purpose is to

[Means for solving problems]

In order to solve the above problems, the present invention is characterized in that the throttle valve opening degree is set in multiple stages according to various conditions in a throttle valve opening degree control device.

Specifically, using FIG. 1 of the present invention as an example, the throttle valve opening control device is a diaphragm device equipped with a rod 21 that comes into contact with a throttle valve lever 13 that rotates integrally with the throttle valve 12. The throttle valve opening degree is set according to the pressure acting on the negative pressure chamber 24 of this diaphragm device 2.

A negative pressure path 3 is provided in the negative pressure chamber 24 of the diaphragm device 2.
is connected, and this negative pressure path 3 opens upstream of the throttle valve 12 when the opening degree of the throttle valve 12 is equal to or higher than the first set opening degree Or, and opens upstream of the throttle valve 12 when the opening degree of the throttle valve 12 is less than the first set opening degree Or. It communicates with a negative pressure port 31 that opens downstream.

The negative pressure chamber 24 also includes an atmospheric passage 4 communicating with the atmosphere.
is connected.

An on-off valve 5 is interposed in this atmospheric passage 4,
The on-off valve 5 disconnects the atmospheric passage 4 in response to an output signal from an arithmetic unit 6 that generates a signal according to various conditions.

The arithmetic unit 6 issues a signal to cause the on-off valve 5 to communicate with the atmospheric passage 4 in order to communicate the negative pressure chamber 24 with the atmosphere during cold times, and causes the on-off valve 5 to communicate with the atmospheric passage 4 under conditions other than cold times. At a duty ratio of , a signal is issued to connect and disconnect the atmospheric passage 4.

The throttle valve 12 is at the first set opening when cold.
The opening degree is controlled to Or, and the opening degree is controlled to a second set opening degree Ou which is smaller than the first set opening degree Or under conditions other than when cold.

[Effect]

During cold conditions, the on-off valve 5 fully opens and communicates the atmospheric passage 4 in response to a control signal from the arithmetic unit 6, so that atmospheric pressure acts on the negative pressure chamber 24. Therefore, the amount of movement of the rod 21 of the diaphragm device 2 becomes maximum, and the opening degree of the throttle valve 12 is set to the first set opening degree Or.

After warming up, the arithmetic unit 6 drives and controls the on-off valve 5 at a predetermined duty ratio using signals according to various conditions, so the on-off valve 5 communicates with the atmospheric passage 4.
The pressure acting on the negative pressure chamber 24 is set to a predetermined value. Therefore, the rod 2 of the diaphragm device 2
1 becomes smaller, and the opening degree of the throttle valve 12 is set to the second set opening degree Ou, which is smaller than the first set opening degree Or.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a system diagram showing the overall configuration of a throttle valve opening control device according to an embodiment of the present invention.

A bench lily 11 is formed in the carburetor intake path 1 . A throttle valve 12 is pivotally supported downstream of the bench lily 11 and rotates in accordance with the amount of operation of an accelerator (not shown) provided in the vehicle interior to control the opening area (passage area) of the carburetor intake passage 1. ing. 1
4 is the closing direction of the throttle valve 12 (counterclockwise in the figure)
It is a return spring that biases the 13 is a throttle valve lever that rotates integrally with the throttle valve 12. 15 is in contact with the throttle valve lever 13 and the throttle valve 1
This is a throttle adjustment screw that sets the minimum opening degree of 2, that is, the idle opening degree O.

2 is a diaphragm device that controls the opening degree of the throttle valve 12.

The diaphragm device 2 includes a rod 21 whose one end abuts against the throttle valve lever 13, and the other end of the rod 13 is fastened to a diaphragm 22. The inside of the diaphragm device 2 is separated by a diaphragm 22 into an atmospheric chamber 23 and a negative pressure chamber 24 . 25 is a spring that always urges the diaphragm 22 downward in the drawing.

A negative pressure path 3 is provided in the negative pressure chamber 24 of the diaphragm device 2.
is connected. This negative pressure path 3 is the negative pressure port 3
1 is connected. 32 is an aperture.

The opening position of the negative pressure port 31 is determined by the opening degree of the throttle valve 12 determined when the throttle valve lever 13 comes into contact with the rod 21 protruding by the maximum amount, that is, the first setting. When the opening degree is equal to or higher than the opening degree Or (commonly referred to as a touch opening degree), the opening is opened upstream, and when the opening degree is less than the first set opening Or, it is opened downstream.

Further, an atmospheric passage 4 is connected to the negative pressure chamber 24, and one end of this atmospheric passage 4 is connected to, for example, an air horn 16 upstream of the bench lily 11 or an air cleaner (not shown).

An on-off valve 5 is interposed in the middle of the atmospheric passage 4.

This on-off valve 5 has a structure that blocks the atmospheric passage 4 in response to a signal output from the computing device 6, and when the atmospheric passage 4 is communicated, atmospheric pressure acts on the negative pressure chamber 24 to shut it off. The structure is such that the action of atmospheric pressure stops when this happens.

The arithmetic unit 6 is a so-called microcomputer connected to the battery B via ignition switches I and G, and receives signals corresponding to various conditions of engine components, auxiliary equipment attached to the engine, and the like.

Examples of signals input to the calculation device 6 include a negative pressure signal a detected by a negative pressure sensor V provided in the intake passage 1, a temperature signal b of a water temperature sensor W that detects the cooling water temperature of the engine E, and a power steering signal. A power steering operation signal c outputted from the driving oil pump P, an engine rotation speed signal d outputted from the igniter S, an air conditioner operation signal e outputted from the air conditioner compressor A, and a temperature sensor provided in the exhaust catalyst device T. Examples include the catalyst temperature signal f detected from H.

The operation of this embodiment based on the above configuration will be explained.

When the throttle valve 12 is at the opening degree O _R in the running state, the negative pressure port 31 is located upstream of the throttle valve 12 where intake pipe negative pressure does not act, so the negative pressure chamber 2
4 is at approximately atmospheric pressure, and the rod 21 protrudes downward in the figure due to the biasing force of the spring 25. When the vehicle enters a deceleration state from this state and the accelerator (not shown) is released, the throttle valve 12 is rotated counterclockwise in the figure by the elastic force of the return spring 14 and closed.

When the throttle valve 12 is closed to the first set opening Or, the throttle valve lever 13 comes into contact with the rod 21,
The closing speed of the throttle valve 12 from this first set opening degree Or to fully closing is determined by the diaphragm device 2. That is, when the throttle valve 12 is closed and reaches the first set opening Or, since the negative pressure port 31 is located downstream of the throttle valve 12, the negative pressure in the intake passage 1 acts on it. This negative pressure acts on the negative pressure chamber 24 of the diaphragm device 2 through the throttle 32, and the rod 2
1 is the negative pressure acting in the negative pressure chamber 24 and the spring 2
It is gradually pulled upward in the figure according to the set pressure of 5. Along with this, the throttle valve 12 gradually closes,
The throttle is gradually closed until it reaches the idle opening degree O where it comes into contact with the throttle adjust screw 15.

In this manner, the diaphragm device 2 functions as a dart pot during deceleration, thereby avoiding sudden closing of the throttle valve 12 and suppressing deterioration of deceleration feeling and exhaust purification performance.

Next, the idle up function will be explained.

For example, when the temperature signal detected by the water temperature sensor W is input to the calculation device 6 and it is determined that the engine cooling water temperature is below a predetermined value, that is, it is cold, the calculation device 6 A signal is output to bring the on-off valve 5 installed in the air passage 4 into the "open" state, that is, to open the air passage 4.

Therefore, atmospheric pressure acts on the negative pressure 24 from the air horn 16 or an air cleaner (not shown), and the diaphragm 22 constituting the diaphragm device 2 is pressed downward according to the set pressure of the spring 25, and the rod 21 is Projecting below the maximum amount. At this time, the negative pressure port 31 is located downstream of the throttle valve 12 which is at the idle opening degree O, and the negative pressure is applied to the negative pressure path 3.
, which acts on the negative pressure chamber 24 through the atmospheric pressure passage 4, but is offset by the atmospheric pressure acting from the atmospheric passage 4.

As mentioned above, if the throttle valve lever 13 comes into contact when the rod 21 protrudes the maximum amount, the throttle valve 12
Since the opening is set to the first set opening Or (touch opening), the idle up amount at this time is the maximum.

Therefore, since the amount of fuel supplied from the carburetor is increased, even if fuel adheres to the wall of the intake passage, a sufficient amount of fuel can be supplied to the combustion chamber.
It is possible to stabilize engine rotation.

Further, by supplying the rich air-fuel mixture, components such as an exhaust catalyst installed in the exhaust passage downstream of the engine combustion chamber can be quickly warmed up, so that exhaust purification performance can be improved.

When the idle is increased under conditions other than when the engine is cold, that is, when the idle is increased to suppress a decrease in the idle rotation speed when the air conditioner or power steering is operated, the computing device 6 adjusts the duty ratio to a predetermined duty ratio. The on-off valve 5 issues an output signal to communicate or cut off the atmospheric passage 4.

Under such conditions, the opening degree of the throttle valve 12 is determined by the intake passage negative pressure acting from the negative pressure port 31;
It is set based on the pressure balance with the atmospheric pressure acting from the atmospheric passage 4. That is, the negative pressure acting on the negative pressure chamber 24 from the negative pressure port 31 is weakened by the atmospheric pressure acting from the atmospheric passage 4, and the diaphragm device 2
The rod 21 is held at a position where the opening degree of the throttle valve 12 is set to a second set opening degree Ou which is smaller than the first set opening degree Or.

At this time, the time ratio for driving the on-off valve 5, that is, the duty ratio, is set according to the output signals from each sensor input to the calculation device 6, and the pressure in the negative pressure chamber 24 is kept approximately constant. The communication with the atmospheric passage 4 is cut off so that this occurs.

With the above configuration, the throttle valve 12 is set to the first set opening under conditions other than when cold.
Since the opening degree is controlled to the second set opening degree Ou, which is smaller than Or, the amount of idle increase after warming up can be set to the minimum necessary.

Therefore, the amount of increase in engine speed is prevented from becoming extremely high, and it is possible to suppress the generation of noise and the deterioration of fuel efficiency due to an increase in fuel consumption due to the increase in engine speed.

As described above, according to this embodiment, various engine conditions, such as cold conditions or post-warm conditions, can be adjusted by using a conventionally used throttle valve opening control device equipped with a diaphragm device. Due to the difference, the opening degree of the throttle valve 12 during idling, that is, the amount of idle up can be controlled in multiple stages.
It is now possible to set the required throttle valve opening, suppressing deterioration in warm-up performance due to insufficient idle up when the engine is cold, as well as engine noise and deterioration in fuel efficiency due to excessive idle up after warming up. can do.

In addition, since the throttle valve opening can be set according to various operating conditions using a single diaphragm device,
This avoids complicating the device structure and increasing costs.

Although specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and includes various embodiments within the scope of the claims. For example, the idle up opening degree when the auxiliary equipment is driven, that is, the second set opening degree Ou, does not necessarily have to be limited to one opening degree, but can be changed depending on the output signals of various sensors that detect engine conditions. The opening degree may be set to multiple stages by changing the duty ratio of the on-off valve drive. By controlling the drive in this way, when multiple loads from the air conditioner or power steering are applied at the same time, the throttle valve opening can be adjusted to the
By opening the valve at an arbitrary position between the set opening degree and the second set opening degree, it is possible to further suppress a decrease in the idle rotation speed.

〔Effect of the invention〕

As described above, according to the present invention, by controlling the opening degree of the throttle valve in multiple stages according to various conditions of the engine, the opening degree of the throttle valve is adjusted according to all operating conditions from cold time to after warm-up. This makes it possible to suppress deterioration in warm-up performance due to insufficient idle increase when the engine is cold, and generation of engine noise and deterioration of fuel efficiency due to excessive idle increase after warm-up.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing the overall configuration of a throttle valve opening control device according to an embodiment of the present invention. 12... Throttle valve, 13... Throttle valve lever, 2...
...Diaphragm device, 21...Rod, 24...
Negative pressure chamber, 3... Negative pressure path, 31... Negative pressure port, 4
...Atmospheric path, 5...Opening/closing valve, 6...Arithmetic unit,
Or...first set opening degree, Ou...second set opening degree.

Claims (1)

[Scope of Claims] 1. A throttle valve that includes a rod that comes into contact with a throttle lever that rotates integrally with the throttle valve, and that is equipped with a diaphragm device that sets the throttle valve opening depending on the pressure acting on the negative pressure chamber. In the opening control device, the negative pressure chamber of the diaphragm device opens upstream of the throttle valve when the opening of the throttle valve is equal to or higher than a first set opening, and opens downstream of the throttle valve when the opening is less than the first set opening. A negative pressure path that communicates with the negative pressure port that is connected to the engine is connected to an atmospheric path that communicates with the atmosphere. An on-off valve is interposed to control the opening of the throttle valve to the above-mentioned first set opening by communicating with the atmospheric passage based on the output signal of the arithmetic unit when the cold is on. Under other conditions, the atmospheric passage is communicated/blocked at a predetermined duty ratio based on the output signal of the calculation device, and the throttle valve opening is set to a second set opening, which is smaller than the first set opening. A throttle valve opening control device characterized by controlling.