JP3403084B2 - Vehicle with continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a control device for an internal combustion engine having a continuously variable transmission, and more particularly to a control device for when an abnormality occurs in a throttle opening detecting means. About what you did. 2. Description of the Related Art Recently, a continuously variable transmission (Continuously Varia
BLE Transmission (hereinafter referred to as CVT), and a transmission that can smoothly change the gear ratio steplessly has been developed. Compared with a so-called manual transmission or automatic transmission that changes the gear ratio stepwise, the CVT has the advantage that there is no shift shock and that the engine can be driven in an optimal operating state, and drivability is improved. And fuel efficiency. However, the speed ratio of the CVT is normally automatically controlled by a dedicated CVT controller (transmission control means) as disclosed in Japanese Patent Application Laid-Open No. 5-294175. At least the throttle opening is used as a parameter. Therefore, the throttle opening signal output from the throttle sensor is
Although it is necessary to input the throttle opening signal to a T controller, conventionally, a throttle opening signal is input to a CVT controller or the like via an engine controller that controls the ignition timing of the engine, the fuel injection amount, and the like. That is, the engine controller normally functions as a buffer for the throttle opening signal as viewed from the CVT controller. [0004] However, when an abnormality occurs when the throttle sensor comes off or breaks down, the engine controller detects this abnormality and performs fail-safe processing. However, the CVT controller cannot detect the above-mentioned abnormality because the CVT controller passes through the engine controller serving as the buffer. [0005] Therefore, even when an abnormality occurs in the throttle sensor, the CVT controller cannot determine that an abnormality has occurred and performs normal control. Was sometimes worse. SUMMARY OF THE INVENTION In order to solve such a problem without changing the existing hardware configuration, the present invention provides a continuously variable transmission from an engine control means for controlling an internal combustion engine. The transmission control means is notified of the abnormality of the throttle opening detection means by using an idle switch signal output to the transmission control means for controlling the throttle opening. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has an internal combustion engine as a power source, a continuously variable transmission capable of freely changing a gear ratio, and detecting a throttle opening and having a value corresponding to the opening. Throttle opening detection means for outputting a throttle opening signal; engine control means for controlling the internal combustion engine in accordance with an operating state such as the detected throttle opening; and the throttle opening signal input via the engine control means Transmission control means for controlling a speed ratio of the continuously variable transmission based on the value of the variable speed control, wherein the engine control means has a function of detecting abnormality of the throttle opening detection means. An engine-equipped vehicle, wherein the engine control means takes two values, i.e., whether the vehicle is in an idling state at a normal time, and determines the value of an idle switch signal input to the transmission control means, when the abnormality is detected, At times The switching is performed at a frequency that cannot be generated, so that an abnormality of the throttle opening detection means can be transmitted to the transmission control means. [0008] In this case, the transmission control device can detect the abnormality of the throttle opening detection means without changing the existing hardware configuration, particularly, the wiring and the signal input / output port of each control means at all. This allows the transmission control means to perform an appropriate fail-safe operation related to the gear ratio control. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram mainly showing a portion according to the present embodiment in an automobile as a traveling vehicle.
As shown in FIG. 1, the vehicle uses an engine 1 as an internal combustion engine as a power source, and connects the engine 1 and driving wheels 3 by a continuously variable transmission (hereinafter referred to as CVT) 2. . The engine 1 has its ignition timing, fuel injection amount and the like electrically controlled by an engine controller 5, and its throttle valve is mainly composed of a rotary potentiometer for detecting an opening. A throttle sensor 4 as a throttle opening detecting means is attached. The throttle opening signal a output from the throttle sensor 4 is transmitted at least to a CVT controller 6 described later via the engine controller 5. In the present embodiment, among the throttle opening signals a, those output from the throttle sensor 4 and input to the engine controller 5 are referred to as primary opening signals a1,
A signal output from the engine controller 5 and input to the CVT controller 6 is referred to as a secondary opening signal a2. The engine controller 5 is known as a so-called microcomputer device including a CPU, a memory, an input / output interface, and the like. The engine controller 5 controls the idling speed and the like, and can detect an abnormality such as the detachment or failure of the throttle sensor 4 from the abnormality of the control. The CVT 2 is not limited as long as it can continuously and continuously change the gear ratio. The mechanism is not limited as long as this function is satisfied. For example, in the present embodiment, the input sheave 21 and the output Belt 2 with sheave 22
The one connected by 3 is adopted. The input sheave 21 and the output sheave 22 are
The winding diameter of No. 3 can be freely changed, and by changing this diameter, the speed ratio can be continuously and continuously changed. A sheave driving means 7 for changing the diameter of each of the sheaves 21 and 23 and a CVT controller 6 as a transmission control means for controlling the gear ratio by controlling the sheave driving means 7 are provided. The CVT controller 6 is a so-called microcomputer device comprising a CPU, a memory, an input / output interface, and the like.
And is provided separately. This CVT controller 6
At least the throttle opening is used as the control parameter of the speed change ratio according to, and a secondary opening signal a2 having a value indicating the throttle opening is input from the engine controller 5 for that purpose. Further, an idle switch signal “b” that takes a binary value indicating whether or not the engine 1 is idling is also output from the engine controller 5 and input to the CVT controller 6. The value of the secondary opening signal a2 is normally the value V of the primary opening signal a1 inputted to the engine controller 5.
Same as TH, but if the engine controller 5 determines that the throttle sensor 4 is abnormal due to the throttle sensor 4 being detached or malfunctioning, the secondary opening signal a
The value of 2 is changed by the engine controller 5 to a predetermined value regardless of the value VTH of the primary opening signal a1. In this embodiment, when the engine controller 5 detects the abnormality of the throttle sensor 4 described above, the idle switch signal b is higher than the frequency band which can be generated at the time of the normal idling determination. Switching at the frequency of the band (20 Hz in this embodiment), FIG.
An abnormality of the throttle sensor 4 is transmitted to the CVT controller 6 by generating a pulse waveform as indicated by a middle symbol pls. Specifically, among the control routines stored in the memory of the engine controller 5, a routine for outputting the idle switch signal b is shown in the flowchart of FIG. First, in step S1, it is determined whether or not the throttle sensor 4 is normal. If it is normal, the process proceeds to step S2; otherwise, the process proceeds to step S7. Steps S2 to S6 are for judging whether or not the vehicle is idling as in the prior art. Briefly, in step S2, it is determined whether or not the engine is idling in a cycle before the control cycle. If the vehicle is not idling, the process proceeds to step S3. If the vehicle is idling, the process proceeds to step S4. In step S3, it is determined whether or not the throttle opening TA calculated from the value VTH of the primary opening signal a1 is 1.5 degrees or more. If it is 1.5 degrees or more, the process proceeds to step S5. Otherwise, go to step S6. Step S4
Then, it is determined whether or not the throttle opening TA is 1.1 degrees or more. If it is 1.1 degrees or more, the process proceeds to step S5.
Otherwise, go to step S6. Here, two kinds of reference values (idle opening value) of 1.1 degrees and 1.5 degrees are provided because hysteresis is provided for determining whether or not the engine is idling, and control stability is provided. It is for planning. In step S5, it is determined that the vehicle is not in the idling state, and the value of the idle switch signal b is set to Lo. In step S6, it is determined that the vehicle is in the idling state, and the value of the idle switch signal b is set to Hi. Step S7 is an unconventional control added in this embodiment. That is, step S7
Then, the value of the idle switch signal b is set to H at a cycle of 20 Hz.
i. Switch to Lo. Therefore, according to the present embodiment, as shown in FIG.
Indicates whether or not the engine is idling.
When the abnormality occurs, the value is switched at a frequency (20 Hz in this embodiment) higher than the frequency band which can be generated at the time of idling determination and can be generated at a normal time. This results in the generation of a simple pulse waveform. For this reason, if the CVT controller 6 monitors the change of the value of the idle switch signal b, it is possible to detect an abnormality of the throttle sensor 4 and perform an appropriate fail-safe process relating to the speed ratio control. . As a result, safety and drivability can be improved. Moreover, since the idle switch signal b is used, the present embodiment can be realized only by changing the software without changing the existing hardware configuration, particularly, the wiring and the signal input / output ports of the controllers 5 and 6 at all. Becomes possible. The configuration of each part of the present invention is not limited to the illustrated examples described above, and various modifications can be made without departing from the spirit of the present invention. As described above, according to the present invention, focusing on the fact that the idle switch signal is a binary signal that switches at a relatively low frequency, the value of the idle switch signal is changed to a high frequency. By using the switch as described above, the transmission control means is also used as an abnormality transmission signal for transmitting the abnormality of the throttle opening detection means. Therefore, the existing hardware configuration, particularly the wiring and signal input / output ports of each control means. Can be detected by the transmission control device without any change in the throttle opening detection means. Therefore, even when such an abnormality occurs, it is possible to cause the transmission control means to perform an appropriate fail-safe operation related to the gear ratio control, thereby improving safety and drivability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic overall configuration diagram showing one embodiment of the present invention. FIG. 2 is a flowchart showing a part of control of an engine controller in the embodiment. FIG. 3 is a timing chart showing a time change of a throttle opening signal and an idle switch signal of the embodiment. [Description of Signs] 1 ... Internal combustion engine 2 ... Continuously variable transmission (CVT) 4 ... Throttle opening detection means 5 ... Engine control means (engine 1 controller) 6 ... Transmission control Means (CVT controller) a: throttle opening signal pls: pulse wave

──────────────────────────────────────────────────の Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02D 9/02 341 F02D 9/02 341C 29/00 29/00 D 41/22 310 41/22 310L F16H 59/22 F16H 59 / 22 61/12 61/12 (56) References JP-A-10-213001 (JP, A) JP-A-9-202158 (JP, A) JP-A 9-196955 (JP, A) JP-A-1 92553 (JP, A) JP-A-4-22747 (JP, A) JP-A-5-294175 (JP, A) JP-A-2-23249 (JP, A) JP-A-11-48831 (JP, A) JP-A-11-51172 (JP, A) JP-A-9-162933 (JP, A) JP-A-6-58342 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 9/00-45/00 B60K 41/00-41/28 F16H 59/00-61/12

Claims (1)

(57) [Claims 1] An internal combustion engine as a power source, a continuously variable transmission capable of freely changing a gear ratio, and having a value corresponding to the throttle opening detected and detected. Throttle opening detection means for outputting a throttle opening signal, engine control means for controlling the internal combustion engine in accordance with an operating state such as the detected throttle opening,
Transmission control means for controlling a speed ratio of the continuously variable transmission based on a value of the throttle opening signal input via the engine control means, wherein the engine control means includes a throttle opening detection means. A vehicle with a continuously variable transmission having a function of detecting an abnormality, wherein an engine control means takes two values as to whether or not the vehicle is in an idling state in a normal state and inputs the idle value to the transmission control means. Change the value of the switch signal
A vehicle with a continuously variable transmission, wherein when the abnormality is detected, the transmission is switched at a frequency that cannot be generated in a normal state, so that the abnormality of the throttle opening detection unit can be transmitted to the transmission control unit.