JPS6355333A - Throttle valve controller - Google Patents

Abstract

PURPOSE:To enable traveling even upon malfunction of an electronic control actuator, by driving first and second drive gears in a differential gear arranged on a throttle valve shaft through independent driving means. CONSTITUTION:A differential gear 5 is coupled through a gear 4 to the valve shaft 3 of a throttle valve 2. An acceleration wire 12 connected to an acceleration pedal 13 is coupled with a first drive gear 6 which engages with the differential gear 5, and an electronic control actuator 8 containing a D.C. motor 81 is coupled to a second drive gear 7. Since first and second drive gears are driven independently, open/close control of the throttle valve is not disabled even upon malfunction of one drive means.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a throttle valve control device, and more particularly to a device for controlling a throttle valve of a vehicle engine using an electronically controlled actuator.

[Conventional technology]

Recently, as part of engine control to improve exhaust purification performance and fuel efficiency, the mechanical connection between the throttle valve and the accelerator pedal has been eliminated, and a signal (accelerator depression amount signal) that converts the accelerator depression amount into an electrical quantity and other engines. 2. Description of the Related Art Throttle valve control devices using electronically controlled actuators that control the opening and closing of throttle valves in response to signals representing operating conditions or vehicle running conditions (for example, engine speed signals, gear position signals, etc.) are being developed.

[Problem that the invention seeks to solve]

In the conventional throttle valve control device using an electronically controlled actuator as described above, the opening and closing of the throttle valve is performed by a drive motor that operates upon receiving commands from the arithmetic control unit. In order to achieve responsiveness and the driving force required to open and close the throttle valve, the driving motor is comprised of a drive motor having a driving torque of a predetermined value or more, and a transmission mechanism 1 for this driving force, usually a reduction gear device. Therefore, in order to have high-speed response and generate the driving force necessary to open and close the throttle valve, a high-speed motor is required if the reduction ratio of the reduction gear device is set to a large value, and a high-speed motor is required if the reduction ratio is set to a small value. A large motor is required to generate this, and in any case, there are problems in that it is expensive, large, and heavy.

Furthermore, there were the following problems from a safety perspective.

In this electronically controlled actuator-based throttle valve control device, opening and closing of the throttle valve is controlled by a vehicle control device comprising a calculation control section that sequentially calculates the optimum opening degree in response to signals representing engine operating conditions or vehicle running conditions. Since this is done by a drive motor that operates in response to a command, it is necessary to install a safety device to prevent the vehicle from running out of control even if the electronically controlled actuator becomes inoperable while the vehicle is running. Examples of such safety devices include (1) ) A configuration in which a return spring is attached to the throttle shaft to return the throttle valve to the closed position when control is stopped.

(2) A configuration that includes an electromagnetic clutch that disconnects the throttle shaft from the electronically controlled actuator when control becomes impossible.

(3) A configuration in which a return spring and an electromagnetic clutch are combined and the return spring is activated when the electromagnetic clutch is disengaged is disclosed in JP-A-55-145867.

However, in these conventional examples, once the electronically controlled actuator becomes inoperable, it is possible to prevent the vehicle from running out of control, but it is not possible to maintain stability, and it is also impossible to move the vehicle to a predetermined location for repair. There was a problem with it disappearing.

This invention was made in order to solve such conventional problems, and it is possible to maintain running even when the electronically controlled actuator becomes inoperable, thereby achieving high reliability (and at the same time, high-speed response). Another object of the present invention is to provide an excellent throttle valve control device.

[Means for solving problems]

A throttle valve control device according to the present invention has a valve shaft for opening and closing a throttle valve that varies the output of an engine, and first and second driving gears, and is provided to drive the valve shaft. It is equipped with a differential gear device and a driving means for rotating the first and second driving gears independently.

[Effect]

The differential gear device according to the present invention has a first gear which is rotationally driven by independent drive means. It has a second driving gear, and the output shaft of this gear drives the valve shaft for opening and closing the throttle valve, so even if the driving means for driving one driving gear becomes in a failure state, the output shaft of this gear drives the valve shaft for opening and closing the throttle valve. Since the throttle valve can be opened and closed, the opening and closing operations of the throttle valve will not become impossible immediately. In addition, during normal operation, the throttle valve can be opened and closed by the combined driving force of the driving means that rotates the first and second driving gears independently, so the opening and closing speed of the throttle valve is faster than before. It is possible to realize something with excellent responsiveness.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) is the air intake pipe of the engine (not shown), (2) is the throttle valve, (3) is the valve shaft for opening and closing the throttle valve (2), and (4) is the valve shaft (3). )
The gear coupled to (5) is a differential gear. 611
゜ω is a bevel gear, which is rotatable on each axis (to), and is a bevel gear 611. ■The first and second lines are placed on the outer periphery of
The driving gears t6) and +71 are in mesh with each other. The above axis (
(to) is supported by a bearing, and is fixed to the shaft Q so that the pinion shaft ω is perpendicular to the shaft Q. A small bevel gear mark, vI, is attached to the pinion shaft (to), and the small bevel gears ω and ■ are the above-mentioned bevel gears 511.1! It meshes with +3. Also, both ends of the pinion shaft (to) are the valve shaft (to) of the throttle valve (2).
3) is fixed by a large gear (■) which is rotationally driven via a gear (4). (9) is a rotating shaft fixed to the axis of the first driving gear (6), and the groove of the segment type disc fixed to the rotating shaft (9) with bolt αD is connected to the accelerator wire @
is applied, and this wire α2 is connected to an accelerator pedal α3. (The god is a spiral return spring placed on the rotating shaft (9) to apply tension to the accelerator wire @. This spring α gradient generates a torque in the direction of returning the throttle valve (2) to the closed position on the rotating shaft ( 9). (151 is a return spring for the accelerator pedal αJ, and αe is a stopper for the accelerator pedal α3. The first driving gear (6) is a mechanical connection that responds to the accelerator pedal αJ operated by the driver. It is configured to be rotationally driven by means.

(8) is an electronically controlled actuator, which is composed of a DC drive motor υ and a current control circuit @ that supplies current to it. αη is an opening sensor such as a potentiometer that detects the opening of the throttle valves (2) and (7), and its output signal H is input to the current control circuit @.

The ring is a sensor mark that detects the engine operating state (for example, rotational speed N) and the running state of the vehicle (for example, vehicle speed ■),
The output signals from the sensor O9 that detects the amount of depression of the accelerator pedal (13) operated by the driver are input, and predetermined arithmetic processing is performed on the values of these input signals to determine the target of the throttle valve (2). This is an arithmetic control unit that outputs the opening H A drive current that operates the drive motor (81J) that drives the second driving gear (7) is output from the current control circuit (2).

Next, the operation of this invention will be explained. The rotational driving force of the electronically controlled actuator (8) is generated by the driving gear (7) of @2.
, bevel gear ■, small bevel gear (to), pinion shaft (5
51 and the gear (4) of the valve shaft (3) via the large gear (to).
) is transmitted. At this point, assuming that the bevel gear 5υ does not rotate, that is, that the depression of the accelerator pedal 03 is kept constant, the target throttle opening Ht is set according to the two signals H and Ht input to the electronically controlled actuator (8). The opening and closing of the throttle valve (2) is electronically controlled by the above-mentioned transmission path so that

The movement of the throttle valve (2) follows the instruction of the target opening H (with some response time delay).

On the other hand, when the degree of depression of the accelerator pedal αJ changes, the accelerator wire ■ is connected to one bevel gear track of the differential gear device (5) via the first driving gear (6) of the segment disc αO1 according to this movement. Driving power is provided. This rotational force acts on the small bevel gears ■ and @, and moves the pinion shaft (to) to the bevel gear 51 in a manner superimposed on the rotation of the bevel gear @, which is being rotated by the child control actuator (8).
J is rotated in the same direction by half the angle of rotation, and the throttle valve (2) is opened and closed via the large gear (2) and the gear (4) in the same manner as above. The movement of the throttle valve (2) in response to the depression of the accelerator pedal αJ is performed in a manner superimposed on the movement by the electronically controlled actuator (8), but the speed of response is different from that of the accelerator pedal 113, excluding slack and play in the accelerator wire @. The movement of J will respond immediately.

In order to make it easier to understand the movement of the throttle valve (2) according to the above explanation, we will explain the accelerator pedal depression degree A, the rotation angle θ by the electronically controlled actuator, the actual opening H of the throttle valve +21, and the target opening of the throttle valve (2). FIG. 2 shows an example of a temporal change in each movement of the degree Ht.

Figure 2 (a) and (b) show A and θ and H and H[ on the same time axis, and A and θ shown in Figure 2 (a)
The shape corresponding to the superimposed angle of and θ is shown in Figure 2 (b).
In the figure, the opening degree H of the throttle valve (2) is changing.

If the target throttle opening degree H is specified, the accelerator depression degree A
It is output after inputting and processing the signals of the sensor aε, but the processing speed of the microcomputer normally used as the calculation control unit (■) is sufficiently fast.
It is faster than the mechanical operating speed of the throttle valve (2).

As described above, this invention has the ability to follow the instructions of the target throttle opening Ht, which changes rapidly, but the speed of change in rotation angle of the input shaft rotationally driven by the electronically controlled actuator is slow (as shown in Fig. 2(a)). (see change in θ). Therefore, as an electronically controlled actuator, if a mechanism with a sufficient reduction ratio is provided on the output side of the drive motor, a very low-torque motor can be used, and the drive control circuit also handles a small current, which improves the overall performance of the device. A small and highly safe product can be obtained. Further, if a well-known 71-monic drive mechanism is used as a mechanism for obtaining a large reduction ratio, the size can be further reduced and control accuracy can be improved.

According to the above embodiment, even if one of the drive means 1, for example, the electronically controlled actuator (8) fails, the accelerator pedal α
Since the throttle valve (2) can be opened and closed by the other driving means, which is a mechanical coupling means that rotates the first driving gear (6) in response to the rotational speed of the first driving gear (6), a highly reliable system can be realized. Further, by combining the rotational driving force of the electronically controlled actuator (8) and the driving means responsive to the accelerator pedal αJ, an engine with excellent high-speed response can be realized. Furthermore, since the throttle valve (2) is operated mechanically in response to the response of the accelerator pedal α3 operated by the driver, it is possible to provide a good accelerator response. In addition, conventionally, 1. Internal combustion engines for vehicles have been operated at idle, or when the air conditioner or large electrical load is turned on.

In order to suppress fluctuations in engine speed when the load on the engine suddenly changes due to OFF, another engine output variable means is added, but according to the present invention, it is possible to By making the throttle control device operational, there is also the effect that it can be easily realized without changing the structure of the intake system of a conventional engine.

In addition, although the example uses a bevel gear as the differential gear device (5), the present invention is not limited to this.

In addition, we have shown an example in which the forward motion of the differential gear relative to the original motion is equal for the two original motions, but if you use a differential gear device that changes this ratio, you can emphasize high-speed response to accelerator operation. Alternatively, it is possible to adjust the weight of throttle controllability by electronic control from the electronically controlled actuator side.

〔Effect of the invention〕

As described above, according to the present invention, the valve shaft includes a valve shaft for opening and closing a throttle valve that varies the output of an engine, and first and second driving gears, and is provided to drive the valve shaft. By comprising a differential gear device and a drive means for independently rotationally driving the first and second driving gears,
The first and second driving gears are driven independently, and even if there is a failure in the driving means that drives one of the driving gears, the opening/closing operation of the throttle valve will not become impossible immediately, making it highly reliable. can be realized. Furthermore - first, second
By combining the rotational driving forces of the driving means for driving the driving gears, it is possible to obtain a throttle valve control device with excellent high-speed response.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a throttle valve control device according to an embodiment of the present invention, and FIG. 2 is a characteristic diagram showing temporal changes in the operation of the device according to an embodiment of the present invention. (21... Throttle valve, (3)... Valve stem, (
5)...Differential gear device, (6)...First driving gear, (7)...Second driving gear, (8)...Electronic control actuator, αri...Accelerator Wire, α3...
・Accelerator pedal, αη...throttle opening sensor,
■...Arithmetic control section. ((8) ~ constitutes the driving means.)

Claims (3)

[Claims] (1) A differential gear device having a valve shaft for opening and closing a throttle valve that varies the output of the engine, first and second driving gears, and provided to drive the valve shaft; A throttle valve control device comprising a driving means for rotating a first and a second driving gear independently. (2) The driving means for the first driving gear is a mechanical coupling means that rotationally drives the first driving gear in response to an accelerator pedal operated by a driver. Throttle valve control device as described in . (3) The throttle valve control device according to claim 1 or 2, wherein the driving means for the second driving gear is an electronically controlled actuator.